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Cahill, Paul C. "The economics of fisheries and fisheries management : a partial review." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63301.
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Pascoe, Sean David. "A bioeconomic analysis of the UK fisheries of the English Channel." Thesis, University of Portsmouth, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264457.
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The purpose in this thesis was to undertake a bioeconomic analysis of the fisheries of the English Channel. An economic survey of the fishery was undertaken to establish the economic and financial performance of the various fleet segments in the fishery in 1994-95. It was found that the fishery as a whole was producing negligible levels of resource rent, although some boat owners were receiving intra-marginal rents. Long run equilibrium models of sole and plaice were developed and the optimal (profit maximising) level of effort (in beam trawl hours equivalent) was estimated. It was found that the optimal level of effort was substantially lower than the current level of effort expended on these two species. A method for estimating surplus production models which incorporate decreasing returns to effort was also developed and applied to the fishery. A linear programming (LP) model was also developed which incorporate the multi-species and multi-gear features of the fishery. The model was used to estimate the maximum level of profits that could be achieved in the fishery given existing stock conditions. It was found that profits could be increased substantially, but at the cost of a large reduction in fishing employment. A compromise `optimal' was estimate using multi-objective (goal programming) techniques. The LP model was also used to estimate the effects of a restriction on days at sea and reduced total allowable catches of sole and plaice. It was estimated that these policies would impose additional costs on various segments of the fishery, particularly the trawl segments to which they are targeted. Benefits, if any, were likely to be negligible as the policies were estimated to result in increased discarding rather than decreased catch. The model results suggest that the long term level of effort may be more effectively reduced through implementing a charge on access to, or use of, the resource.
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Torres, Julio Alejandro Pena. "Economic analysis of marine industrial fisheries." Thesis, Queen Mary, University of London, 1996. http://qmro.qmul.ac.uk/xmlui/handle/123456789/28956.
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This thesis is a collection of essays on the problem of overfishing in multifirm fisheries with a common property fish stock. We focus on the case of marine industrial fisheries, where the costs of preventing free riding tend to preclude cooperative harvesting. We study the overfishing problem by analysing harvesting incentives that stem from variations in (i) technological (cost, production and biological growth) functions, (ii) institutional factors (access schemes, regulatory agencies' instruments and their monitoring and enforcement powers, harvesting competition), and (iii) objective functions (private firms' planning horizons, welfare functions). Chapter 2 discusses conditions under which a fishing collapse can occur and examines the commonly held argument that fishing collapse is a public bad. Chapter 3 studies Chilean fishing regulations over the last five decades. The regulator's persistent inability to enforce annual quotas is analysed. Distributive disputes and triggered lobbying powers are examined. The late 1980s controversies over a new Chilean fishing law are analysed in-depth from this perspective. Chapter 4 explains the main motivations and key assumptions leading us to the oligopoly harvesting models of chapters 5 (static setting) and 6 (dynamic setting). These models focus on a deterministic single fish species and a single sector harvesting fishery composed of profit maximizing and price taking private firms that compete with each other by following non-cooperative harvesting strategies. These models examine the overfishing rankings that result from comparing Cournot-Nash and Stackelberg equilibria. First best and second best welfare benchmarks are considered. The Cournot-Nash setting is intended to illustrate a large number oligopolistic fishery, while the Stackelberg equilibrium is meant to be a first approximation to analyse the implications of harvesting fisheries subject to industrial concentration. Empirical evidence suggesting the presence of industrial concentration in a series of important marine industrial fisheries is described in chapters 3 and 4.
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Dawson, Robert Donald. "Vertical Integration in Commercial Fisheries." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/28627.
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Vertical integration has received much attention in the last 25 years and there are well-known theories that explain this behavior. However, the one common thread that runs through virtually all of this research is the assumption of private property rights. Very little attention has been paid to how firms behave when the property rights structure under which they operate changes. The commercial fishing industry is a prime example of an industry where property rights have shifted. Due to problems of over-fishing and over-capitalization, economists have championed the conversion of fisheries from common property or open access resources, to private property through the use of quota programs.
Research shows that quota management is effective in reducing capitalization in fisheries, yet there are questions about other effects the programs might have. Among these is a concern over increased vertical integration. Some argue that this is leading to a loss of the independent fisherman that is a part of U.S. history, much like family farms. There is also concern that increased vertical integration is in turn leading to decreased competition in these markets; by owning the quota that is required to fish, processors are increasing their power over the market for unprocessed fish. In response to these and other concerns, the United States Congress imposed a moratorium on the implementation of individual transferable quota-style (ITQ) programs in 1996. Speculation aside, however, there is no empirical evidence to confirm or refute that the use of quota management actually leads to increased vertical coordination.
Three fisheries are used as case studies to analyze what affects the decision to vertically coordinate in commercial fisheries. The traditional reasons for vertical integration are to lower transaction costs or to foreclose a market. But now a new factor, shifting property rights, is also considered. Results indicate that the individual characteristics of the fishery are more important than the management or property rights regime itself. This gives some direction to designing management programs that meet our desire to reduce over-capitalization and over-fishing, yet avoid increasing vertical coordination, all the while minimizing the loss of resource rent in the fishery.Ph. D.
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Greenville, Jared William. "Marine Protected Areas: A Tool for Fisheries Management." Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/1893.
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The management of fisheries has progressed over the past century in an attempt to solve the problem of open access. A range of controls, both economic and non-economic in nature, have been used to ration the use of marine resources. Unfortunately, many controls have failed to correct open access problems. Whilst a recent development in fishery control, protected areas defined as an area with a fishery free of extractive pressure, have been put forward as an arrangement which may, in conjunction with other controls, be used to overcome the over-exploitation of marine resources. Marine protected areas have been advocated in areas where other forms of fishery management are impractical or unsuccessful (Sumaila 1998). Arguments for protected area use are based around the heterogeneous nature of fisheries, uncertainties in marine populations and as a hedge strategy to reduce risks of over-exploitation (Conrad 1999a). Through the protection of biodiversity, improving the resilience of the ecosystem, protected areas may mitigate the effects of negative shocks (Ludwig et al. 1993 and Bostford et al. 1997). Further, protected areas have been suggested as a means to manage uncertainty and environmental stochasticity (Grafton and Kompas 2005 and Grafton et al. 2005). The protection of biomass and habitat has the potential to improve fishery returns even when stocks are not overly exploited, with the benefits accruing even from small-sized protected areas (Grafton et al. 2005). The use of marine protected areas as a management tool has resulted from a recognition that it is important to preserve biological habitats as well as stocks. From a societal point of view, the use of protected areas should be evaluated in the context of changes in resource rent and improvements in welfare. As fishery resources are often owned by a common group, usually society, management objectives should be to maximise the return from use of the resources, whether for extractive or non-extractive purposes. Given this decision criterion, protected areas can be evaluated in the sense of opportunity costs and benefits. Protected areas will influence the return from fishery resources through changes in access to fishing grounds, and thus harvest, effort and resource rent. Once a protected area is established, the flow of biomass from the protected area to the remaining fishing ground, may increase biomass, influence the effects of uncertainty and stochasticity, thus effecting mean harvests, effort and resource rent may increase. Changes in resource rent are dependent on other controls. Protected areas are a ‘blunt’ policy instrument, in the sense that they are not an instrument to capture resource rent or change the incentives of fishers. Models of marine protected areas in fisheries vary in complexity, however, a few key elements are necessary in analysing the effects of protected area creation. First, multi-species interactions have the potential to be significant in determining the outcome from a protected area; second, effort expended in the fishery must be dynamic, that is, it must be endogenously determined by the model as fishers will respond to changes in rent brought about through the establishment of a protected area; third, institutional structures that govern the expenditure of effort within a fishery will play an important role in the effectiveness of protected areas in increasing the resource rent of a fishery; and fourth, environmental stochasticity and uncertainty need to be included in the analysis. A stochastic and deterministic model of a predator-prey meta-population fishery was developed to analyse the effects of protected area creation within a fishery. Such a model has not previously been used to analyse protected area creation. The model was analytically solved to find the optimal biomass of each species in an individual patch. This allowed for a comparison of protected areas under a range of management controls ranging from those which led to open access fishing to those which led to an optimal steady-state biomass. The model allowed for linkages between sub-populations based on differing density related flows. Further, due to the linkages between species on both environmental and economic grounds, the effect of protected areas on different groups which target different species could be analysed. The benefits from protected area creation were classified into unique and non-unique benefits. Unique benefits were defined as those which solely flow from the use of a protected area as a tool in fisheries management. Two unique benefits were defined: • Improvements in the resilience of the fishery; and • Reductions in environmental stochasticity. The ability of a protected area to both improve the resilience of the fishery, and smooth fluctuations in environmental stochasticity have been shown to lead to increases in mean resource rent. Thus, protected areas were shown to form part of an optimal fisheries management structure. Generally, the resilience benefits were maximised for small-sized protected areas, whereas the reduced environmental stochasticity benefits were maximised for larger protected areas. The dispersal system between the protected area and the fishing ground affected the unique benefits from protected area creation. Sink-source dispersal increased the unique benefits from protected area creation, as stock movements occurred independently of relative population densities. The independent flow improved the ability of the protected area to hasten the return of the fishery to a steady-state and lessened the variation of harvests in the open fishing grounds. However, in the case where the protected area led to large differences in population densities, and if the area formed a sub-population that was linked to the surrounding fishing ground by density-dependent dispersal, the unique benefits are likely to be greater than under sink-source dispersal. The non-unique benefits were defined as those which could be obtained from other control mechanisms. These benefits were non-unique as they could be achieved from more stringent controls on fisher behaviour. The determinants of the non-unique benefit in terms of dispersal were the same as for the unique benefits. However, the economic conditions of the fishery determined the magnitude of the non-unique benefits. For fisheries with sub-optimal biomass, the unique benefits were greater than those with optimal steady-state biomass. The non-unique benefits identified from protected area creation were: • Changes in biomass towards optimal levels; • Changes in species biomass ratios towards optimal levels; and • Changes in effort towards optimal levels. Protected areas in fisheries may be an optimal policy choice to achieve the non-unique benefits of protected area creation. Protected areas, it has been argued, are a relatively low cost management tool, due to the lower monitoring and enforcement costs. Thus, the use of protected areas offer a solution to the problems of over extraction of fishery resources for lower transaction costs, which may erode the non-unique benefits under different policy instruments. If this is the case, then a protected area larger than is required to maximise the unique benefits of protected area creation could form part of an optimal fisheries management strategy. Whether the protected area is larger or smaller than the size that maximises both the unique and non-unique benefits of protected area creation would depend on the level of transaction costs involved in using alternative policy instruments. Protected areas were found to have distributional effects on the fishery due to changes in the species biomass ratio towards the predator species post protected area creation. The creation of a protected area will have distributional effects on the fishing industry if different fisheries target the different species separately. Fishers targeting predator species are likely to gain from the establishment of a protected area, as now the aggregate level of stocks of this species is greater, leading to both greater unique and non-unique benefits. For fisheries that target prey species, the benefits of protected area creation are lessened. The increased predation within protected area boundaries limited the unique benefits of the protected area. The low cost nature of a protected area will influence the portion of the fishery used for this type of control given an optimal policy programme. If protected areas are relatively low cost in comparison with other controls they should be used relatively more intensely. Further, the use of protected areas may hasten the evolution of fisheries away from open access exploitation towards controls which maximise the value of the fishery. With lower transaction costs, the ability to adopt protected areas over other forms of management is greater, and by doing so, the movement towards optimal exploitation will improve the discounted value of the fishery. The analysis presented in this thesis examined the benefits of protected areas to fisheries. The focus of the study was placed on the benefits to flow to a fishery if a protected area was used as a tool for wild-harvest fisheries management. Marine protected areas also have the potential to generate a range of other benefits, such as recreational values, non-use values, and potential improvements in consumer surplus from fish caught within fisheries that use protected areas. These other benefits would need to be considered when determining whether or not a protected area should be created in a fishery.
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Bwalya, Samuel Mulenga. "The experimental analysis of the political economics of fisheries governance /." View online ; access limited to URI, 2005. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3188837.
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Lam, Vicky Wing Yee. "Global fisheries economics in the face of change in climate." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45587.
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Climate change and changes in biogeochemical conditions of the ocean lead to changes in distribution of marine species and ocean productivity. These changes would affect fisheries, food security, livelihood of fishing communities and eventually the whole economy in different countries. This thesis uses simulation modelling to assess the direct impacts of change in physical and biogeochemical conditions of the ocean on marine fisheries and the socio-economic implications at both global and regional scales.
I develop a new global database of fishing cost, and provide an overview of current fishing cost patterns at national, regional, and global scales. The outcomes lay the foundation for the subsequent economic analysis in the thesis, and should also be useful for other future fisheries economic studies. Using these results and other data from the Sea Around Us Project, I estimate the change in landings of over 800 species of fish within the Exclusive Economic Zones (EEZs) under climate change scenarios based on dynamic bioclimate envelope model (DBEM), and an empirical model. About 75% of EEZs are projected to show declines in landings under the Special Report on Emission Scenario (SRES) A2. Most of them are in developing countries, which are socio-economically more vulnerable to climate change.
In West Africa, which is one of the most vulnerable regions to climate change, our model projects that there will be a reduction in landings in the 2050s, with some countries experiencing declines of more than 50% under the “business-as-usual” scenario. This substantial decline not only affects the food supply and security in the region, but also has a negative impact on employment opportunities and the downstream economic impact on the whole society. I also analyze how change in climate and ocean acidity under scenarios of anthropogenic CO₂ emission is expected to affect the economics of marine fisheries in the Arctic region. My model only projected a slight decrease in catch potential of marine fish and invertebrates under the impact of ocean acidification in the 2050s. Future studies accounting for the synergistic effects among climate change, ocean acidification and other factors on marine ecosystems are needed.
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Garrod, Brian. "An economic evaluation of fisheries policy in the United Kingdom." Thesis, University of Portsmouth, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332795.
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Herrera, Guillermo E. "Spatial structure and informational asymmetry in the economics of multiple stock renewable resources /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/7425.
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Manning, Peter Robert. "Managing Namibia's marine fisheries : optimal resource use and national development objectives." Thesis, London School of Economics and Political Science (University of London), 1998. http://etheses.lse.ac.uk/2639/.
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Prior to independence, Namibia's marine fisheries had suffered over-fishing, typical of open access exploitation of a common pool resource where there is excess demand. The Namibian Government's policy objectives seek optimal sustainable use of Namibia's fisheries resources and a substantial increase for Namibians of benefit from these resources. In assessing the appropriateness of Namibia's fisheries management system for meeting these objectives, state involvement in the management of the resource is considered, the biological and ecological constraints of the resource are examined and the degree to which national management of fisheries is nested in a global system of fisheries governance is defined. Empirical evidence establishes the critical importance of successfully managing these resources through environmental shocks and the importance for the industry of sufficient economic flexibility, often hindered by overcapacity, to cope with those shocks. Even at low, sub-optimal biomass levels, evidence suggests that substantial resource rent accrues to industry as abnormal profit, or finances overcapacity. Government attempts to redistribute benefit from the resource have been only partly successful. These findings establish the importance of state intervention to ensure that capacity is reduced as close as possible to a bio-economic optimal level, thus maximising resource rent. Collection by the state of a larger proportion of available resource rent would make it less possible for abnormal profits to be earned and make rent less available for financing over-capacity. The additional state finance, representing benefit from the resource, could be directed by the state towards more effective usage in the development process. The management of Namibia's marine fisheries will best be achieved by working towards a system of co-management between the state and industry, providing a framework for nested institutions tailored to the conditions of each fishery, in a joint endeavour to generate a socially optimal use of the resource.
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Shamshak, Gina Louise. "Economics of bluefin tuna aquaculture in the United States /." View online ; access limited to URI, 2009. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3368006.
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Abiodun, A. "Fishermen's job perception and mobility : a study in socio-economics and fisheries management." Thesis, University of Aberdeen, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.592038.
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This thesis sets out to examine contending issues in the literature on fisheries resource exploitation and management and, in recognition of the critical role of labour in executing a successful policy of rational utilisation of the resource, to investigate the fishermen's perception of their occupation and probable determinants of their mobility. This is placed within the context that labour stickiness, even in the presence of declining economic returns, is the rule rather than the exception in the fishing industry. These issues are examined with data on Scottish and Nigeria's fishing industries and a survey of Scottish fishermen. It is found that the issue of fishermen's mobility is not that of a lack of willingness on the part of the majority to exit from the industry but the problem is mainly with the speed of exit which may be too slow to match the requirements of management for stock conservation. This is reflected in the high degree of tolerance to declining income among the fishermen, an equivalent of a low reservation wage which translates to a high cost of inducing exit from the industry. Models investigated for fishermen's mobility in Scottish fisheries indicate the strong influence of the opportunity wage, output and vessels on the number of fishermen while for Nigeria's small-scale fisheries the dominance of the output variable coupled with the non-significance of price per se suggests the importance of production for subsistence rather than for exchange. The significance of the unemployment variable is indicative of the open-access nature of the artisanal fisheries of less developed countries. Policies that seek to reduce labour use in the industry may find greater success in vessel reduction for large-scale fisheries but success hinges on the availability of fishing or sea-related alternative employment opportunities.
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Palfreman, David Andrew. "Key economic issues in fisheries development : lessons from projects in Vanuatu, Malawi and Ecuador." Thesis, University of Hull, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384927.
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Al-Oufi, Hamed Said. "Social and economic factors influencing the emergence of collective action in a traditional fishery of Oman : an empirical assessment of three coastal fishing towns in south Al-Batinah." Thesis, University of Hull, 1999. http://hydra.hull.ac.uk/resources/hull:3871.
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Overexploitation of many fish stocks underlines the need for more effort directed towards stock management so that the sustainability of resources is assured. To avert the tragic consequences of overfishing in coastal waters, a growing body of theoretical and empirical research provides evidence in support of cooperation among resource users to manage their commons. This study aimed to investigate the factors that contribute to the emergence and evolution of collective action in fishermen's communities to manage their coastal fish resources in South Al-Batinah, Sultanate of Oman. The study emphasises the importance of a collective action approach to fish resource management with examples from three fishing towns.In order to understand why fishermen choose to participate (or not to participate) in local collective action to manage fish resources, the researcher focuses on six main sets of issues that influence fishermen's decisions: economic factors; awareness of resource exploitation problems; institutional rules in use; social identity, group size and heterogeneity among resource users. Social and demographic factors as well as vessel configuration were also considered.Data collection for the study was carried out using three methods: questionnaire, semi-structured interview and observations of fishermen's activities. Statistical reports and other research papers carried out in Oman were also reviewed. The study found that there is a management institution that governs the fishing activities of the fishermen in the study area. Fishermen in the area inherited an indigenous management institution, which was established hundreds of years ago. It was also found that fishermen were very aware of the resource exploitation problems. High awareness of the resource exploitation problems coupled with high interdependence among users might induce them to work collectively to mitigate harm to their long-term welfare.The results of testing a number of hypotheses indicated that among the reasons which may influence collective action, are high economic dependence on the fishery,individuals' social identity as fishermen, awareness of the resources exploitation problems, risk aversion and heterogeneity (differences in objectives and interests).The study findings indicated that individuals using common resources are faced by various "assurance" and "chicken" problems. In both the PD game and the Assurance game, the preferred outcome is mutual cooperation. Whereas the predicted outcome of the former is defection, the latter suggests the possibility that the preferred outcome (i.e., cooperation) will occur, because individuals' decisions in the commons are influenced by a complex set of factors, rather than strictly materialistic self-interest. The analysis presented in this study examined several of those factors for their influence on individual behaviour. The findings of this study strongly suggest that the presence of local management institutions to coordinate the fishermen's activities in the study area is the key factor in avoiding the worst outcome (universal defection). The game structure has been changed from a Prisoner's dilemma to a Privileged game or a game of Chicken where the benefits from cooperation are maximized. It is the role of the institutions to determine how the cost of providing the public goods might be shared among participants.
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Schnier, Kurt E. "Economic analysis of spatially heterogeneous resources: The case of the fishery." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280326.
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This dissertation investigates the implication of combining economic and ecological models in an effort to expand our knowledge of the complex problems associated with resource management. The motivation for this research arises from the perceived need to develop a better understanding of how the flow dynamics within a resource affect the efficient management of that resource. Following the introduction, the second chapter experimentally tests the theoretical models of agent behavior in patchy resource environments under both sole-ownership and competitive extraction regimes. In each setting experimental results indicate that subjects over-allocate vessels to regions that possess the greatest rates of emigration within the bioeconomic system relative to the theoretical predictions. This introduces a "spatial externality" because over-harvesting in one region reduces the harvest in the surrounding regions. The third chapter proposes a potential solution to the problems associated with a spatial externality by analyzing the use of marine reserves in the presence of a heterogeneously distributed resource. This is conducted by introducing the presence of biological "hot spots" (areas within a fishery that possess a larger growth potential than the surrounding areas) with spatial rates of migration into the current economic theory. Simulation results indicate that the presence of biological hot spots within a fishery creates an environment within which it is optimal to establish a marine reserve that increases the value of the fishery. The fourth chapter makes use of my earlier experimental and simulation research, which indicate that locational choice and the spatial distribution of effort should affect the management of the fishery. Within this chapter a spatial Heckit model is developed to empirically investigate for the presence of herding behavior among yellowfin sole and Pacific cod fishermen in the Eastern Bering Sea. Econometric results provide support for herding behavior among fishermen within the yellowfin sole fishery. Moreover, fishermen respond to the lagged biomass and spatially weighted biomass signals as significant determinants of locational choice. This results in Lotka-Volterra oscillations in the Pacific cod fishery. In the final chapter of this dissertation, the general findings are concluded and some future avenues of research are discussed.
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Paulsen, Sandra Silva. "Topics on the ecological economics of coastal zones : linking land uses, marine eutrophication, and fisheries /." Uppsala : Dept. of Economics, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200773.pdf.
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Sherif, Souad Mohammed. "The economic feasibility of introducing aquaculture into traditional farming systems in Arizona." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/288781.
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The primary objective of this study was to evaluate the economic feasibility of introducing fish culture into irrigated cotton production on farms in central Arizona. The representative farm adopted in this study is a cotton farm described in Arizona Field Crop Budgets, 1994-95. The only adjustment necessary for the farmer to make is to keep water in the ditches at all times. Water as a production variable for fish production was thus calculated only for the additional quantity required. Analysis of these production systems was accomplished by budgeting procedures as well as statistical analysis. The economic-engineering (synthetic firm technique) was employed to develop the input-output coefficients necessary for analysis. Five fish densities and eight ditch capacities were tested. The production function was estimated using input and yield data. Three functional forms (linear, quadratic and Cobb-Douglas) were examined to determine how well they estimated the production system. Using budget analysis, a fish stocking density of six fish per cubic meter and a ditch capacity of 2,925 m3 appear to provide the optimal production scenario, if the percentage of fish reaching harvestable size is improved from 66 percent to at least 80 percent. This density has been proven to require minimum production costs and to provide the most efficient use of resources. However, production functions estimated in this study indicate that profits can be increased through additional use of feed. At any ditch capacity, a density of six fish per cubic meter, provides the optimal economic results, MVP = PX2 Finally, the implication of the findings of this study are that raising tilapia in irrigation ditch systems on cotton farms in central Arizona is feasible at a stocking density of six fish per cubic meter. Studies to improve the percentage of fish reaching marketable size at this density is very critical. Increasing the initial size of the fingerlings could be a consideration in improving the percentage of fish reaching marketable size and eventually increasing optimum economic returns.
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Queiroz, Greiziene Araújo. "O circuito inferior da economia urbana = a pesca no município de Ilhéus - BA." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/286926.
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Orientador: Márcio Antonio CataiaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências
Made available in DSpace on 2018-08-19T20:18:31Z (GMT). No. of bitstreams: 1 Queiroz_GreizieneAraujo_M.pdf: 4576573 bytes, checksum: 8de4282b467a778c9c217e2e0214af9a (MD5) Previous issue date: 2011
Resumo: O objetivo norteador deste trabalho é compreender as dinâmicas econômicas ligadas à pesca, que geram trabalho e renda para uma boa parcela da população do município de Ilhéus-BA. Tendo como foco o circuito inferior da economia urbana. Ilhéus tem parte de sua economia baseada em um circuito espacial produtivo pesqueiro local e regional. Nesse sentido, nossa pesquisa aborda o circuito inferior da economia urbana, cuja variável-chave é a produção do pescado. Esta é exercida por trabalhadores autônomos ou através de relações de trabalho em parcerias, que utilizam pequenas quantias de capital e meio de produção simples, com tecnologia e metodologia de captura pouco mecanizada e baseada em conhecimentos empíricos. Para caracterizar a pesca em Ilhéus foi necessário considerar: a pesca como atividade de resistência, o período técnico-científico informacional, o perfil socioeconômico dos pescadores, os agentes não hegemônicos da economia urbana e as diversas atividades envolvidas na formação de um circuito espacial produtivo (produção, circulação, troca e consumo). Assim, o circuito inferior da pesca oferece à população pobre de Ilhéus subsistência, ocupação e renda, através do uso do território como abrigo
Abstract: The guiding objective of this work is to understand the economic dynamics fishing-related, which generate jobs and income for a good portion of the population of the city of Ilhéus-BA. Focusing on the lower circuit of the urban economy, Ilhéus has part of its economy based on a regional and local fisheries productive space circuit. In this sense, our research focuses on the lower circuit of the urban economy, whose key variable is the production of fish. This is carried out by self-employed or through a working relationship in partnerships that use small amounts of capital and means of simple production, with technology and methodology of capture little mechanized and based on empirical knowledge. To characterize the fishing in Ilhéus, it was necessary to consider: fishing as resistance activity; the technical-scientific-informational period, the socioeconomic profile of the fishermen, the non-hegemonic agents of the urban economy and the various activities involved in the formation of a productive space circuits (production, circulation, exchange and consumption). Thus, the lower circuit of fishing offers to the poor population of the Ilhéus livelihood, occupation and income through use of the land as shelter
Mestrado
Análise Ambiental e Dinâmica Territorial
Mestre em Geografia
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Stark, Alyson N. "The Consequences of Increasing Ocean Acidification on Local and Global Fishing Industries." Scholarship @ Claremont, 2010. http://scholarship.claremont.edu/cmc_theses/70.
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As human activities continue to generate accelerating levels of carbon dioxide emissions, the world’s oceanic resources are threatened by variability in seawater chemistry, known as ocean acidification. Recent increases in atmospheric carbon dioxide have resulted in decreased carbonate ion concentrations and ocean pH levels, leading to increasingly acidic waters. The exact consequences of these chemical changes on ecosystems and individual species are difficult to predict; however, research has shown that economically valuable calcifying species will experience reduced reproductive fitness and population declines. Ocean acidification, therefore, poses an immediate risk to both fish stocks and fishery industries. From a local perspective, individual regions will need to implement dynamic management strategies to prepare for anticipated economic consequences. In a global context, international cooperation is required for further research and collaborative efforts must be made to reduce future acidification.
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Wang, Wen-Kai. "Application of stochastic differential games and real option theory in environmental economics /." St Andrews, 2010. http://hdl.handle.net/10023/893.
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Turay, Foday. "An economic analysis of artisanal fisheries management alternatives in west Africa : the case of the marine pelagic fishery in Sierra Leone." Thesis, University of Portsmouth, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306941.
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Boas, Andrew, and n/a. "Institutions, cooperation, and the quota management system." University of Otago. Department of Geography, 1994. http://adt.otago.ac.nz./public/adt-NZDU20070531.130233.
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The purpose of this thesis is to analyse the evolution of New Zealand�s Quota Management System (QMS) for marine fisheries. Analysis is performed using institutional theory and methodology.
A broad review of institutional theory is made. In contrast to neoclassical economic theory, of which institutionalists have been a major voice of dissent, institutionalism stresses a holistic approach to policy analysis. An understanding of the the forces for institutional change and the structure of that change are the primary focus of institutionalism.
An institutional framework for understanding the common pool nature of fishery resources is adopted. This highlights how the physical and technical characteristics of the resource and related decision-making arrangements influence the patterns of human interaction that determine the outcomes of a management regime such as the QMS.
It is shown that the QMS was adopted in 1986 to address the biological crisis that had occurred because of past open access management policies. The fiscal crisis and the economic ideology prevailing at the time were also influential in promoting the QMS. The system was not able to be expanded as was intended because of a series of challenges from Maori disputing the Crown�s right to fishery resources. The Deed of Settlement signed in 1992, has supposedly settled Maori claims to commercial fisheries and allowed expansion of the QMS.
Assessing the QMS using the institutional framework developed, showed the strong influence that neoclassical ideology has played in determining the outcomes achieved. Inadequate information concerning biophysical, social and economic implications of fishing constrain the ability of the QMS to successfully manage the resource. Inconsistencies and inadequacies in the legislation are only just being addressed as part of a comprehensive legislative review process.
The future development of the QMS is also addressed in terms of the likelihood of cooperative common property management regimes being adopted. The common pool nature of the fisheries makes common property management regimes preferable. Cooperative community cultures are claimed by institutionalists to improve the outcomes achieved in common property regimes. There was considered, however, to be only limited potential for cooperation within the current institutional structure for New Zealand�s fisheries. Although the changes of the legislative review appear to be making some progressive changes, the diversity of interest groups and the prevailing western culture are seen as potential impediments to a comprehensive cooperative regime.
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Ganter, Sylvain. "Modelling the Grand Banks commercial fishing fleet: Fleet structure, fishing performance and economic viability." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28165.
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The Grand Banks commercial fishing industry has been faced with several crises in the past decades. These crises have included the major financial crunch and inflation of the late 1970s and early 1980s, as well as the resources collapse of the Northern cod stock and other groundfish stocks in the 1990s followed by the foreign fishing disputes of the mid 1990s. The thesis examines the evolution of the fishing industry in Atlantic Canada during these critical years with focus on the fisheries of the Grand Banks. A linear programming model of the configuration of the Grand Banks commercial fishing fleet is formulated to describe the post 2000 period. The model is driven using the results of an extensive analysis of historical records for this recent period. The model results are validated by comparing them with historical average annual data over the period 2000-2005. The linear programming model is run under several scenarios emulating changes in government policy and economic conditions affecting the harvesting sector. Based on the results, alternative fishing fleet configurations for the Grand Banks fishery are defined to improve the economic viability of the fishing fleet. The model pointed to changes in fleet configuration including a rationalization of the shrimp and crab fleets and a shift to longline vessels with higher-valued product for groundfish harvesting. Once implemented, these suggestions would advance the goals of the new "Oceans to Plate" approach to fisheries management recently announced by Fisheries and Oceans, Canada.
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Nemoto, Keiichi. "Modeling the impacts of area closures on the Hawaii longline fishery a spatial-temporal economic model incorporating fish movement /." Thesis, University of Hawaii at Manoa, 2002. http://proquest.umi.com/pqdweb?index=1&did=765044511&SrchMode=1&sid=3&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1209150203&clientId=23440.
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Elsler, Laura G. "Multi-level Interactions between Fisheries and Trade : Modeling intertwined social-ecological systems." Licentiate thesis, Stockholms universitet, Stockholm Resilience Centre, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-159470.
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Sustainable and equitable fisheries are central for addressing the challenges of the UN Sustainable Development Goal 14: Life Below Water. International trade, once presented by Walrasian economists as a panacea for fisheries development, has not markedly decreased poverty and has been related to the overexploitation of marine species. In this light the consequences of a continued expansion of seafood trade are highly uncertain and problematic. Two competing theoretical hypotheses predict either overexploitation or recovery of marine species when connected to international trade, respectively. The empirical literature finds trade relationships and connections of local fisheries to a large-volume market critical factors for social-ecological outcomes. Here, I combine these insights to show that multi-level links, between fishers & different markets (market manuscript) and marine species & trade relationships (squid manuscript), are critical to explain diverging social-ecological outcomes. In the market manuscript we model the transition from local, to multi-level (both local and global), to global markets in a two species fishery. We find this transition is non-linear, leading to fluctuations in species abundance as a result of abrupt switches between target species. Critical fluctuations of species abundance driven by new market connections are a result of large shifts in prices for one species and high asymmetries in expected income between the two species. The squid manuscript provides empirical and modeling evidence that cyclical changes in the ocean can drive social-ecological systems outcomes through changing interactions at multiple levels. The interactions between squid population and fishers and squid distribution and trading structures determines benefit distributions in the fishery. The lack of consideration of multi-level interactions related to trade in models for fisheries management is likely associated with a lack of processes for integrating the empirical and theoretical insights of two disciplines at the core of fisheries science. Social-ecological system scholars study more often empirical and fishery economics the theoretical aspects of interactions between trade and fisheries. One process suggested in this thesis to bridge insights from both disciplines in fishery models is the careful study of the important interactions in the empirical case. Comparison of these interactions with observed empirical interactions in other systems informs the model conceptualization that is then embedded in a theoretical framework. This leads to the development of models of intermediate complexity that integrate insights on regular structures and patterns observed in real social-ecological systems. The squid manuscript exemplifies this integration. We integrate observed multi-level links in a standard fishery model between the squid population fishers and traders, and thus better represent the empirical system. A continuous dialogue between empirics and theorycan help build models of intermediate complexity. To capture the complex elements of these social-ecological systems, in this young field of study, next to a continuous dialogue priority observed empirical dynamics can help question theoretical assumptions. This study seeks to contribute to the development of fisheries management models more suitable to face contemporary challenges of fisheries management by focusing on how multi-level interactions between fisheries and trade shape sustainable and equitable outcomes.
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Little, Alyson Susan. "Impacts of spatial management and economics on discards, landings and fishing location choice : the case of the Scottish demersal fisheries." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=226896.
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Thang, Hnin Julee. "A Cost-Benefit Analysis of Measures to Improve Fishing in Fresh Water : A case study from the Torne, Kalix and Byske Rivers." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64704.
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Freiherr, von Gagern Cyrill Antonius. "Ecological and economic impacts of distant water fishing: three empirical studies." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/283544.
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En la segona meitat del segle XX, la industrialització dels vaixells pesquers va donar lloc a una sobreexplotació dels recursos marins a les àrees costeres dels estats tradicionalment pesquers. En conseqüència, els països pesquers industrialitzats van començar a explorar les aigües llunyanes, en gran part sense traves legals, per alimentar la creixent demanda de peix i marisc. Amb l'entrada en vigor de la Convenció de les Nacions Unides de 1982 sobre el Dret del Mar (UNCLOS, en anglès), així com l’Acord de Recursos Pesqueres (“Fish stock agreement”) de les Nacions Unides de 1995, es van reestructurar radicalment els drets i les responsabilitats de la pesca de captura marina. No obstant això, aquestes noves legislacions van deixar molt d’espai a l’explotació econòmicament ineficient i ecològicament insostenible dels recursos pesquers. En tres assaigs, aquesta tesi dóna llum a la interacció entre les flotes industrialitzades d'aigües llunyanes i les regions sovint vulnerables on s’hi pesca.
El primer assaig revisa críticament el desenvolupament de la pesca en aigües llunyanes en el món tropical durant els darrers 50 anys i ofereix una anàlisi quantitativa de la relació entre les flotes d'aigües llunyanes i els països tropicals d’acollida. Es conclou que hi ha un clar canvi de poder dels països tradicionalment pesquers als nouvinguts, sobretot asiàtics, i que els països petits i econòmicament febles són els més vulnerables a relacions d'explotació amb els estats que pesquen en aigües llunyanes. El segon assaig aborda la qüestió de si, des d'un punt de vista econòmic, els Països Insulars del Pacífic (PICs, en anglès) haurien de continuar concedint accés als estats pesquers d'aigües llunyanes, o si s'hauria d'intentar desenvolupar una indústria pròpia pesquera nacional. Amb aquesta finalitat, un nou model bioeconòmic amb múltiples espècies i actors és analitzat. Els resultats del model mostren que els PICs maximitzarien els seus beneficis mitjançant l'eliminació gradual dels acords d'accés amb els estats pesquers d'aigües llunyanes, substituint-los per un esforç pesquer nacional. L'alternativa és elevar considerablement les tarifes d'accés, tot i que, per descomptat, això pot tenir diferents conseqüències a llarg termini. En el tercer assaig, es descriu un model empíric per inferir el pes viu de la pesca de la tonyina vermella a l’Atlàntic Est i al Mediterrani (EBFT, en anglès) a partir de dades mensuals del comerç entre 2005 i 2011. En base a la captura total estimada, s’arriba a la conclusió que l’EBFT ha estat persistentment sobreexplotada al llarg de tot el període esmentat.
En conclusió, aquesta tesi ha contribuït a la literatura tot estudiant l'impacte de la pesca en aigües llunyanes sobre la salut de les poblacions de peixos en alta mar i en les zones econòmiques exclusives en regions tropicals, així com en el benestar dels països en desenvolupament que són abundants en recursos pesquers.In the second half of the 20th century, the industrialization of fishing vessels led to an over-exploitation of marine resources in near-shore areas of traditional fishing nations. As a result, industrialized fishing nations started to explore distant waters, largely unhindered by legal boundaries, to fuel the growing demand of fish and seafood products. While the coming into force of the 1982 United Nations Convention on the Law of the Sea (UNCLOS), and the 1995 United Nations “Fish Stocks Agreement”, dramatically restructured rights and responsibilities of marine capture fisheries, they left much room for economically inefficient and ecologically unsustainable exploitation of fisheries resources. In three essays, this thesis sheds light on the interplay between industrialized distant water fleets and the often vulnerable regions where they fish. The first essay critically reviews the development of distant water fishing in the tropical world over the past 50 years and provides a quantitative analysis of the relationship between distant water fleets and tropical host countries. It concludes that there is a clear shift in powers from traditional fishing countries to mainly Asian newcomers, and that small and economically weak countries are most vulnerable to exploitative relationships with distant water fishing nations. The second essay addresses the question whether, from an economic point of view, Pacific Island Countries (PICs) should continue granting access to distant water fishing nations or whether they should attempt to develop an own domestic fishing industry. To this end, a newly developed multispecies, multiplayer bioeconomic model is analyzed. It provides the insight that PICs would maximize their profits by phasing out access agreements with distant water fishing nations, replacing these by domestic fishing effort. The alternative is to considerably raise access fees, although this does of course may have different long term consequences. In the third essay, an empirical model is constructed to derive life catch weight for Eastern Atlantic and Mediterranean Bluefin tuna (EBFT) from monthly trade data for all major countries involved in its trade between 2005 and 2011. Based on estimated total catch we conclude that EBFT has persistently been overfished, throughout the entire period. In conclusion, this thesis has contributed to the literature on the impact of distant water fishing on fish stock health in the high seas and tropical Exclusive economic zones, and on the welfare of resource-rich developing countries.
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Fernandez, Cheryl Joy Jardiolin. "Marine protected area : a case study in north-easter Iloilo, Philippines : a thesis presented in partial fulfilment of the requirements for the degree of Master of Management in Economics, Massey University, Palmerston North, New Zealand." Massey University, 2010. http://hdl.handle.net/10179/1250.
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Marine Protected Area (MPA), as a fisheries management tool has been promoted by both national and local conservationists and has provided de facto illustrations of integrated coastal management (ICM) in the Philippines. However, conflict is inevitable in the implementation of public policy such as the MPA because of contrasting objectives and expectations from various stakeholders. Coupled with non-human (e.g. MPA size) and human (e.g. mismanagement) threats, conflict becomes a hindrance to MPA effectivity. In the Philippines alone, only 10-20% of the 500 MPAs are attaining their objectives. This study presents an overview of MPA management and examines the interaction between the civil society and market forces of institutional arrangements in the case of North-Eastern Iloilo (NI) in the Philippines. It discusses overall scenarios that resemble conflict between various national, local and international sectors, assessing MPA success factors and the expected implications from such implementation. Results from key informant, focus-group discussion and social survey show that there are problems on MPA management in the region. Using data and strategic analyses, it presents that minimisation of conflicts amongst actors should be the primary goal of the NI municipalities. In addition, MPA size and membership to organisations are also significant factors of success. Moreover, the analysis from a simple correlation to complex Principal Component Analysis (PCA) and Canonical Correlation Analysis (CCA) conclude that information on MPA regulation does not directly contribute to the improvement in MPA management. It implies that a focus on informing stakeholders about the benefits of having an MPA and its regulations is ineffective. The focus should be on the reduction of conflict between economic actors - for free riding problems are currently occurring, thus minimising conflict by conflict resolution and proper incentives. However, there are still remaining challenges on MPA management, for not all factors are incorporated on this study. The challenge now is on how to identify the remaining factors and integrate them into policies and implementations to improve the overall condition of coastal communities.
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Wang, Wen-Kai. "Application of stochastic differential games and real option theory in environmental economics." Thesis, University of St Andrews, 2009. http://hdl.handle.net/10023/893.
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This thesis presents several problems based on papers written jointly by the author and Dr. Christian-Oliver Ewald. Firstly, the author extends the model presented by Fershtman and Nitzan (1991), which studies a deterministic differential public good game. Two types of volatility are considered. In the first case the volatility of the diffusion term is dependent on the current level of public good, while in the second case the volatility is dependent on the current rate of public good provision by the agents. The result in the latter case is qualitatively different from the first one. These results are discussed in detail, along with numerical examples. Secondly, two existing lines of research in game theoretic studies of fisheries are combined and extended. The first line of research is the inclusion of the aspect of predation and the consideration of multi-species fisheries within classical game theoretic fishery models. The second line of research includes continuous time and uncertainty. This thesis considers a two species fishery game and compares the results of this with several cases. Thirdly, a model of a fishery is developed in which the dynamic of the unharvested fish population is given by the stochastic logistic growth equation and it is assumed that the fishery harvests the fish population following a constant effort strategy. Explicit formulas for optimal fishing effort are derived in problems considered and the effects of uncertainty, risk aversion and mean reversion speed on fishing efforts are investigated. Fourthly, a Dixit and Pindyck type irreversible investment problem in continuous time is solved, using the assumption that the project value follows a Cox-Ingersoll- Ross process. This solution differs from the two classical cases of geometric Brownian motion and geometric mean reversion and these differences are examined. The aim is to find the optimal stopping time, which can be applied to the problem of extracting resources.
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Cardwell, Emma Jayne. "It's not fish you're buying, it's our rights : a case study of the UK's market-based fisheries management system." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:adffcd93-ad2b-4f74-9d3d-a1b3d49fc264.
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This thesis, submitted for the Doctor of Philosophy in Geography and Environment, presents a case study of the development of the UK's market-based management system for oceanic fisheries. Implemented gradually in the years since 1984, the informal nature of the UK's fisheries management system, which has developed through a number of incremental changes and government-industry "gentlemen’s agreements" rather than clear legislative moves, means that few official policy documents (and perhaps consequently, little academic literature) on the subject currently exist. This thesis traces the material and political processes of market formation, looking at the origin of market-based policies in the theories of bioeconomics and wider economic history. It asks what the implicit assumptions of the economic discipline can – and can't – tell us about the impacts and outcomes of market creation, and using a Foucauldian inspired approach to economic performativity, discusses the role of ostensibly descriptive theories in shaping the world around them. Finally, it calls for a greater geographical engagement with marine issues, and proposes an action-research role for geographers in the politics of the sea.
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Guard, Martin. "Assessment of the artisanal fishery for Octopus cyanea Gray 1849 in Tanzania : catch dynamics, fisheries biology, socio-economics and implications for management." Thesis, University of Aberdeen, 2003. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=232573.
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Catch dynamics, fisheries biology and socio-economic dependence are described for the artisanal fishery for Octopus cyanea at three study sites (Kwale. Jibondo, and Mtwara) along the coat of Tanzania. A total of 23,165 octopuses were measured and sexed from 3,514 individual catches. FIShing effort was shown to be 2.9 times greater at Msangamkuu compared to Jibondo and nearly two times more than Kwale. Number of relaxation days between fishing events, when the octopus stock are able to recover through growth and immigration, was shown to be greater at Iibondo than for the other two sites. Marked reductions in catch landings, mean individual weight, catch per unit effort (kg) and size distributions are reported for Msangamkuu and Kwale when compared to Jibondo. Abundance of octopus was however, higher at the former sites most likely in response to predator and competition release. Stock size and biomass (kg) were calculated for Msangamkuu using a De-Lury depletion method and results extrapolated to the other two sites. Despite higher abundance at Msangamkuu and Kwale mean overall biomass (kg) was 36% and 14% respectively lower tban the mean biomass estimate for Jibondo. Spatial comparison of fishing impacts between sites using a surplus production model suggested Jibondo to be more productive and fishing pressure sustainable. In contrast, Msangamkuu was indicated to be seriously overtished and Kwale somewhere in between. Although, Bhattacharya modal progression analyses separated multiple size modes in monthly samples growth analyses were unsuccessful due to the lack of a clear corresponding pattern of modal progression in monthly size distributions. Length weight relationships varied between sites and sexes. All length weight relationships were negative allometric. Size reductions at Kwale and Msangambru may be impacting on reproductive output with a 40% reduction in the number of mature males at Msangamkuu and 24% reduction at Kwale when compared to Jibondo. Fewer mature females were observed at Msangamkuu and Kwale but even at Jibondo mature females accounted for only 2.2% of the catch. Results suggest spawning activity takes place in deeper water ( > 4m) below the fisbed zone. Nonetheless, enough females would have to reach brooding size at each site to contribute to the reproductive stock. Size at first maturity for females was estimated to be 1800g. Only 3.9% of the octopus at Kwale and 1.2% at Msangamkuu weigh more than 1800g compared to 17% at Jibondo. Fecundity was shown to increase with size. Breeding activity is likely to be year round but maturity peaks were evident for June and July and October to November. The den enrichment experiment indicated a clear preference for concrete dens over PVC pipe. Overall density increased by 10% subsequent to den placement but dens were shown in reef areas not to be limiting. The benefit of den enrichment was therefore ambiguous but could be initiated using a phased approach to gauge effectiveness. The artisanal octopus fisheries make an important contnbution to the local economy. population growth and fisher and trader immigrations were noted as the greatest threats to the octopus fishery by fishers. Awareness of relevant marine resource use issues was shown to be high yet enthusiasm for management varied between sites. The first descriptive details of the octopus fauna of Tanzania are provided. Implications for management of the octopus fishery and a series of proposed management actions are provided for discussion between relevant stakeholders.
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Gallagher, Sarah Elizabeth. "Establishing a culinary market for lionfish species through a market-based organization to mitigate the environmental impacts of the invasive species." Thesis, College of Charleston, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1545140.
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Environmental activists are questioning the management strategies of the invasive Indo-Pacific lionfish (a species complex of Pterois volitans and P. miles) in the western North Atlantic, due to the species' rapidly expanding invasion and steadily growing population. The invasive lionfish species ecological effects are of great concern, as impacts on marine and terrestrial ecosystems trigger population and biodiversity declines. Awareness and research supporting the need for better managerial techniques and response strategies are surfacing among academic groups, forcing critical thought on the best methods of containment and population management.
In response to the lack of information on the marketability of the lionfish species, I propose a thesis that focuses on the creation of a privately funded non-governmental organization (NGO) that will offer a more promising solution for the control of lionfish through the application of effective marketing and educational outreach strategies. An NGO design and program provides more options and greater flexibility than the federal response to date, which as previously mentioned has not been efficient in the management of the lionfish invasion, as it is incredibly difficult for federal agencies to conduct the public promotion and supply-chain building necessary to properly found this operation. The NGO will work to initiate interest in the lionfish through public education and cooperation and incentivize its capture and consumption, by appealing to the supply and demand ends of the culinary market. The overarching goal is to demonstrate how an NGO can successfully alleviate environmental impacts and increase sustainability through the use of market-based initiatives and inter-party cooperation.
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Harrison, Sarah A. "Livelihood strategies and lifestyle choices of fishers along the Mississippi Gulf Coast." Thesis, Mississippi State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3618247.
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This study was initiated to assess the biological, ecological and sociological aspects of the blue crab, Callinectes sapidus, fishery associated with the Pascagoula River Estuary in southern Mississippi. Household surveys were conducted in the cities of Moss Point and Pascagoula, Mississippi, September 2010 to September 2011, to identify, describe and classify subsistence fishing activities associated with the estuary. A stock assessment of blue crab was conducted to determine how biological and environmental variability affect the people engaged in this subsistence fishery.
The study revealed two types of subsistence fishing occurring in the Moss Point/Pascagoula area. The first type involves fishing as a livelihood strategy based on economic dependence, and the second type involves fishing as a lifestyle choice based on economic independence. Both are based on customary and traditional patterns of local resource use and consumption and maintained by reciprocal kinship-based social networks.
The blue crab fishery in the Pascagoula River Estuary was highly variable and exhibited strong seasonal and spatial patterns in distribution and abundance. Subsistence fishers in the region have developed strategies to cope with this biological and environmental variability. These region-specific strategies include but are not limited to: fishing using multiple gears simultaneously (rod and reel and crab nets), freezing fish, relying on other natural resources including agriculture and wildlife, and generalized reciprocity.
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Yeeting, Agnes David. "An economic analysis of the domestication of the tuna fishery - the case of Kiribati." Lincoln University, 2009. http://hdl.handle.net/10182/1493.
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The Western and Central Pacific Ocean (WCPO) is home to the largest tuna fishery stock in the world. However, Pacific Island members of the Western and Central Pacific Tuna Commission (WCPTC) argue that their share of the economic rent from the tuna catches taken out of the Pacific region is very small, being on average only about 6% of the total net benefit, when compared to the share earned by Distant Water Fishing Nations (DWFNs). Kiribati is one of the Pacific Island Countries (PICs), which relies heavily on its fishery for its economic development and sustainability. Kiribati earns 40% - 50 % of its government revenue from fisheries access fees paid by DWFNs for tuna caught in the the Kiribati EEZ. The Government of Kiribati (GoK) believes that Kiribati could get greater benefit if they develop their own domestic tuna fishery. This study uses Cost-Benefit Analysis (CBA) and SWOT Analysis to investigate whether domestication of the tuna fishery is the right move for Kiribati or not. The CBA reported in this thesis adapted a model developed by Campbell (2004) to investigate and evaluate fisheries policy in Papua New Guinea (PNG). However the model in this thesis is reflective of the situation and case of Kiribati. In analyzing the different options identified in this study, the CBA indicated negative (-) NPV(s) for the medium-sized vessel option and positive (+) NPV(s) for the large-sized vessel option. The SWOT analysis however, complemented the CBA by further investigating the tuna domestication options in the economic, social and business and business environment of Kiribati. The SWOT analysis indicated that the existing situation and business conditions in Kiribati appears to favor the small to medium sized vessel options which are less risky than the large purse seine vessel option.
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Wiratama, Nugroho. ""Blue heart ocean": a new technology of coral reef conservation in the implementation of fisheries sustainable economics, case studies jakarta waterfront city north Jakarta." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/10343.
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Valdez-Gardea, Gloria. "People's responses in a time of crisis: Marginalization in the upper Gulf of California." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280024.
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This dissertation explores the creative ways in which particular individuals and the community in general, responds to economic crisis and perceived marginality. It shows how residents of El Golfo de Santa Clara, a small community in the upper Gulf of California, with their meager incomes, fuller utilization of kinship and other social sources, participation in illegal and informal activities, migration, and political participation, are contesting their marginality and resisting the social and economic outcome of state policies in the area. Residents' feeling of frustration and disempowerment increased during the early 1990s. Because of ecological changes and structural adjustment policies the shrimp industry in the Gulf of California collapsed. Household salaries dropped drastically; fishermen were unemployed and families had to look for different strategies to survive. In the midst of the economic crisis residents of El Golfo were told of the decree of a biosphere reserve, which initially had the objective of restricting fishing activity in the area. People's responses involved individual and collective performances and discursive critiques of state authority as represented by the management team of the biosphere reserve. Residents pressed their rights to get involved in the management of the area as well as their rights to get infrastructural services for the town. People's responses show that marginality and poverty had nothing to do with a 'natural' or 'biological' condition, as presented by some earlier anthropological studies of the Mexican countryside, but with a historical economic inequality and the distribution of wealth within the country. The peoples' responses to their economic and political situation underline a critique to their perceived identity as a "rural community" by the managers of the biosphere reserve and authorities that categorized rural people as backward, isolated, uncivilized, and unimportant in the larger social formation. These local responses to the political and economic context suggest that anthropologists should take a more engaged approach in the study of the Mexican countryside.
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Hoeinghaus, David Joseph. "Food web architecture in natural and impounded rivers of the Upper Parana drainage basin, Brazil." Diss., Texas A&M University, 2006. http://hdl.handle.net/1969.1/4845.
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Freshwater ecosystems are some of the most threatened on the planet. Efforts to conserve, restore, or otherwise manage large rivers and the services they provide are hindered by limited understanding of the functional dynamics of these systems. This shortcoming is especially evident with regard to trophic structure and energy flow. In this study I use natural abundances of carbon and nitrogen isotopes to examine patterns of energy flow and food-chain length of large-river food webs characterized by different landscape-scale hydrologic features. Ten locations along an approximately 500 km stretch of the Upper Paraná River Basin, Brazil, provided the setting for this work. Carbon derived from C3 plants and phytoplankton were the dominant energy sources across all webs, but relative contributions differed among landscape types (low-gradient river, high-gradient river, river stretches downstream of reservoirs, and reservoirs). Increases in food chain length corresponded with higher relative importance of phytoplankton derived carbon, likely due to size-structured effects of the phytoplankton-zooplankton-secondary consumer trophic link. River impoundment corresponded with decreased ecological and economic efficiency of fisheries production, an important ecosystem service provided by many tropical rivers.
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Hallwass, Gustavo. "Ecologia humana da pesca e mudanças ambientais no Baixo Rio Tocantins, Amazônia brasileira." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/29992.
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A pesca artesanal de pequena escala (ou subsistência) tem sido historicamente pouco estudada. Poucos estudos buscam compreender os fatores que influenciam a pesca nessa escala. Populações humanas que dependem dos recursos naturais apresentam bom conhecimento sobre o ambiente e os recursos explorados. Barramentos de rios são uns dos principais impactos na pesca de águas interiores, e pouco se sabe sobre esses impactos ao longo do tempo. Portanto, informações das populações locais e da pesca de subsistência podem melhorar e complementar o conhecimento científico sobre a pesca e os impactos causados por barramentos. O objetivo desse estudo é analisar as características da dinâmica da pesca artesanal de subsistência no Baixo Rio Tocantins (Amazônia brasileira) através de entrevistas e desembarques pesqueiros. Testamos a eficiência do conhecimento ecológico local de pescadores através de entrevistas no diagnóstico da dinâmica da pesca e de mudanças ambientais decorrentes de barragens em grandes rios (1º capítulo). Também analisamos o rendimento pesqueiro e as variáveis que influenciam na captura de peixes em cinco comunidades de pescadores artesanais do Baixo Rio Tocantins (2º capítulo). Foram realizadas 300 entrevistas com pescadores de nove comunidades ribeirinhas e registrados 606 desembarques pesqueiros em cinco destas comunidades, em 67 dias de amostragem. Através das entrevistas é possível identificar os peixes mais capturados, as artes de pesca e tamanhos de malhas de redes mais utilizadas pelos pescadores, além da sazonalidade da abundância dos peixes. Houve mudança na composição dos desembarques pesqueiros, 22 anos após o barramento. Através das entrevistas com os pescadores, foi possível identificar também quais espécies de pescado aumentaram (Plagioscion squamosissimus), quais diminuíram (Characidae, várias espécies de pacu), bem como quais desapareceram (Semaprochilodus brama) após o barramento. A produção anual e o rendimento financeiro da pesca foram reduzidos em cerca de 55% após o barramento do rio. A maior parte da variação da biomassa de peixes capturada é explicada pelas variáveis ligadas ao esforço e comportamento do pescador: tempo de pesca (35%), número de pescadores (30%) e a distância até local de pesca (20%). Entrevistas demonstraram ser um método rápido, confiável e de baixo custo para obter importantes informações sobre a pesca e os impactos à jusante de uma hidrelétrica em um grande rio amazônico. O conhecimento ecológico local pode complementar pesquisas ecológicas de longa duração de uma maneira rápida e eficiente. Considerar os pescadores, seu conhecimento e seu comportamento na elaboração de planos de manejo pesqueiro adequados com a realidade local, parece ser a maneira mais promissora de garantir a manutenção da biodiversidade, conservação dos recursos pesqueiros e manutenção da pesca artesanal como atividade econômica.Small-scale artisanal (or subsistence) fisheries have been little studied. Few studies have attempted to understand the factors that influence the fisheries on this scale. Human populations that depend upon natural resources show good knowledge about the environment and the exploited resources. Dams are among the main impacts affecting inland fisheries and there is little knowledge about the impacts of dams on fisheries over time. Information from local populations and subsistence fishing may improve and complement the scientific knowledge on fisheries and dam’s impacts. The aim of this study is to analyze the dynamics of subsistence fishing in the Lower Tocantins River (Brazilian Amazon) through interviews and fish landings. We tested the efficiency of recording fishermen’s local ecological knowledge through interviews for assessment of the fisheries dynamics and environmental changes caused by dams in large rivers (1st chapter). We also analyzed the fishing income and the variables that influence the biomass of fish caught in five fishing communities of the Lower Tocantins River (2nd chapter). We conducted 300 interviews with fishermen in nine riverine communities and recorded 606 fish landings in five of these communities in 67 sampling days. Through interviews it is possible to identify the most caught fish species, the fishing gear and gillnet mesh sizes used by most of the fishermen, and the seasonal fish abundance patterns. The composition of fish landings changed 22 years after the dam’s closure. Through interviews with fishermen, also it was possible to identify the species of fish that increased (Plagioscion squamosissimus), decreased (Characidae, several species of pacu) and even disappeared (Semaprochilodus brama) after the dam’s closure. The annual production and financial income of fishing have been reduced by about 55% after the dam’s closure. Most of the variation in the biomass of fish caught is explained by variables related to the fishing effort and to the fisherman’s behavior , such as fishing time (35%), number of fishermen (30%) and distance to fishing grounds (20%). Interviews with fishermen showed to be fast, reliable and inexpensive methods to obtain important information about the fisheries and the impacts downstream from a dam in a large Amazonian river. The local ecological knowledge of resource users can complement long-term ecological research efficiently. The fishermen, their knowledge and their behavior should be considered when developing fisheries management plans appropriate to local realities. This seems to be the most promising way to ensure the maintenance of biodiversity, conservation of fishing resources, and maintenance of artisanal fisheries as an economic activity.
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Alencastro, Liliana A. "An economic analysis of rebuilding artisanal fisheries the potential for fishermen-based ecotourism in the Galapagos Marine Reserve /." [Gainesville, Fla.] : University of Florida, 2010. http://purl.fcla.edu/fcla/etd/UFE0041221.
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Diop, Bassirou Masseck. "Economie écologique des ressources marines : Le cas de la pêcherie crevettière guyanaise." Thesis, Guyane, 2016. http://www.theses.fr/2016YANE0007/document.
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L'objectif de cette thèse a été de comprendre le fonctionnement économique des pêcheries et de proposer des politiques de gestion des ressources halieutiques. L'attention a été portée essentiellement sur la pêcherie crevettière guyanaise. Une première analyse a été effectuée à partir d'une base de données historique. Les premiers constats ont été que cette pêcherie a été marquée par une forte diminution de son stock, de son effort, de sa production, ce qui a conduit à la fermeture de certaines entreprises. Les premiers résultats ont permis de comprendre que la production de cette pêcherie est fortement dépendante du stock et que la forte diminution de ce dernier n'est pas liée à la surpêche. En effet, malgré une baisse considérable de l'effort de pêche et du prélèvement, le stock a continué de s'effondrer, suggérant ainsi que d'autres facteurs peuvent être mis en cause. En particulier, la zone de pêche est caractérisée par un environnement amazonien avec une mangrove importante et de nombreux cours d'eau. L'intégration de la mangrove dans l'analyse, qui a pourtant connu une diminution de sa surface dans les années 90, n'a pas permis d'expliquer l'effondrement du stock observé. Cependant l'intégration d'autres facteurs comme le débit des fleuves et la température de surface de l'océan ont permis de mieux comprendre la chute du stock dans cette filière. La pêcherie crevettière guyanaise semble en effet fortement impactée par le changement global, notamment l'augmentation de la température des eaux dans les zones de prélèvement. De surcroît, le dernier chapitre suggère que certains phénomènes endogènes à la pêcherie, comme les effets de congestion entre les navires de pêche, rendent l'ensemble de la pêcherie plus sensible à des chocs exogènes technologiques, économiques ou biologiques, en amplifiant l'impact de ces derniers sur les décisions optimales des entreprises concernant l'effort de pêche. Afin de préserver la pêcherie crevettière en Guyane française, il apparaît donc essentiel d'essayer de limiter, dans la mesure du possible, les sources du changement climatique, au lieu de modifier profondément les pratiques économiques du secteurThe objective of this thesis was to understand the economic behavior of fisheries and to propose resource management policies. The focus was mainly on the French Guiana shrimp fishery. First an initial analysis will be performed on a historical data basis. Initial findings have showed that this fishery was characterized by a strong decrease in its stock, its effort, its production and lead to the closure of some companies. The results have helped also to understand that the production in this fishery is highly dependent on stock and the decrease of the stock is not related to overfishing. Indeed, despite a considerable decline in fishing effort and production, the stock continued to slump suggesting that other factors may be involved. In particular the fishing zone is characterized by an Amazonian environment with significant mangrove and many rivers. The integration of mangrove in the analysis, which shows a decrease in its surface in the 90s did not explain the collapse of the stock. However, the integration of other factors such as rivers and sea surface temperatures have increased understanding of stock depletion in this sector. The French Guiana shrimp fishery is highly influenced by global change, notably increasing in temperature. Moreover, the last chapter suggests that some endogenous phenomena in the fishery, like the congestion effects between fishing vessels, make the whole fishery more sensitive to technology, exogenous economic or biological shocks, amplifying their impact on the optimal business decisions regarding fishing effort. In order to save the French Guiana shrimp fishery, it appears therefore crucial to try to limit the sources of climate change instead of deeply modifying economic practices in this sector, which may lead to misunderstandings by fishermen and local political conflicts
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Schuhbauer, Anna Christina. "The economic viability of small-scale fisheries." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/60759.
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Small-scale fisheries (SSF) provide food and jobs for millions of people worldwide and therefore contribute to the wellbeing of many coastal communities. However, there is concern that the benefits they generate may dwindle to nothing because they are currently threatened by overfishing, climate change, industrialization and global market shifts. SSF are politically and economically marginalized as well as understudied. I argue that understanding the economic viability of SSF will help address these challenges.
Currently, the definition of economic viability is incoherent and often equated with financial viability, where profitability is the sole goal. However, SSF are complex dynamic systems whose goal is not always only profit but also social wellbeing and the maintenance of livelihoods play essential roles. Therefore, I define economic viability as the achievement of non-negative net benefits to society over time.
Here I determine the difference between financial and economic viability as the distortion created by the provision of fisheries subsidies. Therefore, I carried out a first global bottom-up assessment that splits subsidy amounts into those received by small- and large-scale fisheries. My analysis suggests that only 16% of global subsidies reach SSF despite their global importance. This disproportionate division of subsidies impairs the economic viability of already vulnerable SSF.
Next I compute what I denote as basic economic viability of SSF using Mexican fisheries as an example. Results suggest that decreasing fishing effort, reducing capacity-enhancing subsidies and improving monitoring and management can lead to increased economic viability of SSF.
To understand the underlying dynamics of economic viability, I extended the economic viability approach and included assessments of economic impacts, employment and food security aspects into the study. Taking these attributes into account, results indicate that SSF are more important to society and have a more positive prognosis for economic viability than their large-scale counterparts.
These findings are relevant, not only for Mexican SSF but for SSF worldwide. The results help bridge the current knowledge gap in SSF research essential to policy making and management that would not only improve economic viability but also the sustainability of the fish stocks upon which they rely.Science, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate
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Raman, Nair R. "An investigative and evaluative study of factors affecting quality of agricultural and farm information services in Kerala." Diss., University of Kerala, 2004. http://www.keralauniversity.edu/.
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Agriculture is not only a country’s backbone of food, livelihood and ecological security systems, but is also the very soul of its sovereignty. In Kerala population density is high and land is scarce. To achieve sustainable advancement in quality of human life, meeting the domestic food requirement is to be given foremost priority in development plans. As the area of cultivation cannot be increased and growth of population cannot be controlled growth in food production is to be achieved by qualitative improvement in farming. This requires improvements in material inputs, farming techniques, storage technology and research. Effective integration of these factors is tied closely to adequate information flow, which can be ensured only by an efficient information system for agricultural education, research, extension and development. So evaluation and improvement of existing information services is very crucial for sustainable agricultural growth. The study evaluates the existing information resources, facilities, services, possibilities for resource sharing, accessibility of external sources, and the factors that affect the quality and efficiency of information services in agricultural sector. Coverage is limited to the State of Kerala. Sample consist 105 institutions of different levels, and information users consisting of 426 scientists and 220 farmers. Different sets of questionnaires and interview schedule were used to elicit information. The study found that agricultural research conducted at various institutions in the region at huge public expense has generated knowledge for improving production. Along with these huge collections of acquired content is also stored in the sector. But when a farmer, an extension worker, a scientist or an administrator needs information it is not easily accessible. The study found that agricultural sector fails to effectively bank on information resources available due to the lack of an information system and network. Recommends an Agricultural and Farm Information System for Kerala. Suggests a model plan for a computer communication network for resource sharing between the agricultural institutions in the State, which will also ensure, smooth flow of results of research down to the grassroots level to achieve maximum productivity in agriculture.
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Nguyen, Quang Van. "Impacts of fisheries management objective on technical efficiency: Case studies in fisheries." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/131191/1/Quang_Nguyen_Thesis.pdf.
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This dissertation is the first to examine the impact of differing fisheries management objectives and potential trade-offs with respect to technical efficiency. Understanding this relationship is important, as fisheries managed with strong social objectives, such as maintaining livelihoods, may, potentially trap individuals in inefficient, low-income production systems. The key conclusions were that fisheries managed with strong economic objectives resulted in higher technical efficiency than those with social objectives. However, other factors (including efficiency estimation methods used, model specifications, input measures) also have an impact on technical efficiency levels. Hence, technical efficiency estimates between fisheries should be compared with caution.
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Du, Toit Elmari. "A quantitative bio-economic investigation of inshore fisheries." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52127.
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Dissertation (PhD)--University of Stellenbosch, 2001.ENGLISH ABSTRACT: The efficient management of renewable resources may ensure sustainable income to communities and countries. In the past the mathematical modelling used in the management decisions, in South Africa, was based on biological considerations only. In this thesis we include economic factors in the models and aim to determine steady state harvesting levels such that a maximum present value of all future revenues may be reached. A bio-economical approach is followed throughout the study and applied to the South African Cape Rock Lobster (Jasus lalandii) resource. We first address the problem using the simplest surplus production models. The model is applied to the Cape Rock Lobster, finding that the economical factors do indeed influence the steady state results, emphasising that they should be incorporated in the modelling process. A more descriptive two-sex-delay-difference model is then applied, which includes delay times for juveniles to reach sexual maturity and distinguishes between sexes. Yet further involved stage-class models are also studied and we propose a solution to the non-linear programming problem reached. These models may assist decision makers in future as knowledge on, for example, the growth of the two sexes, proper size limits and the influence of price differences are gained. Finally, we propose a harvesting strategy where catch is taken from alternative spatial lanes and apply here results from reaction diffusion theory. This theoretical approach might provide guidelines to new and underdeveloped fisheries in future, but also influence current inshore fisheries towards new management strategies.
AFRIKAANSE OPSOMMING: Die doeltreffende bestuur van hernubare hulpbronne kan 'n volhoubare ekonomiese opbrengs aan gemeenskappe en lande verseker. In die verlede is die wiskundige modelle wat in die besluitnemingsproses gebruik is, in Suid Afrika, gebaseer op biologiese oorwegings alleen. In hierdie studie word ook ekonomiese faktore in die modelle ingesluit en word ewewigstoestande bepaal vir vangste, sodanig dat 'n maksimum huidige waarde van toekomstige inkomste uit 'n vissery bereik word. 'n Bio-ekonomiese benadering word deurgaans gevolg en modelle word toegepas op die Suid-Afrikaanse Weskus Kreefbron (Jasus lalandii). Die studie begin deur basiese surplus produksie modelle te gebruik. Die resultate van die toepassing op die Weskus Kreefbron toon dat die ekonomiese faktore 'n groot invloed op die voorgestelde ewewigstoestand van die populasie het. Dit benadruk dus die feit dat hierdie faktore in die modelleringsproses ingesluit behoort te word. Meer beskrywende twee-geslag-vertragings-verskil modelle word daarna toegepas, en sluit in 'n vertragings periode vir vis om 'n volwasse stadium te bereik. Hierdie tydfaktor verskil dikwels vir mannetjies en wyfies en daarom word hier 'n twee-geslag model gebruik. Meer gevorderde klasse modelle word ook bespreek. Ons stel 'n oplossing vir hierdie nie-lineêre programmeringsprobleem voor. Hierdie gevorderde modelle mag in die toekoms handige hulpmiddels wees wanneer inligting rakende 'n spesie gesoek word. Sulke inligting mag insluit die groeitempos van mannetjies en wyfies, geskikte grootte beperkings vir vangste en die invloed van prysverskille vir verskillende groottes vis. 'n Nuwe vangste strategie word ook voorgestel waar vangste slegs geneem word uit alternatiewe ruimtelike bane en pas ons hier resultate uit die reaksie-diffusie teorie toe. Hierdie teoretiese oplossings mag riglyne bied wanneer nuwe visserye in die toekoms ontgin word, maar ook huidige visserye beïnvloed in die rigting van 'n nuwe bestuur strategie.
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McCafferty, James Ross. "An assessment of inland fisheries in South Africa using fisheries-dependent and fisheries-independent data sources." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005072.
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The role of inland fisheries as contributors to local and national economies in developing African countries is well documented. In South Africa, there is increasing interest in inland fisheries as vehicles for achieving national policy objectives including food security, livelihoods provision, poverty alleviation and economic development but there is surprisingly little literature on the history, current status, and potential of inland fishery resources. This lack of knowledge constrains the development of management strategies for ensuring the biological sustainability of these resources and the economic and social sustainability of the people that are dependent on them. In order to contribute to the knowledge base of inland fisheries in South Africa this thesis: (1) presents an exhaustive review of the available literature on inland fisheries in South Africa; (2) describes the organisation of recreational anglers (the primary users of the resource); (3) compiles recreational angling catch records and scientific gill net survey data, and assesses the applicability of these data for providing estimates of fish abundance (catch-per-unit effort [CPUE]); and finally, (4) determines the potential for models of fish abundance using morphometric, edaphic, and climatic factors. The literature review highlighted the data-poor nature of South African inland fisheries. In particular information on harvest rates was lacking. A lack of knowledge regarding different inland fishery sectors, governance systems, and potential user conflicts was also found. Recreational anglers were identified as the dominant user group and catch data from this sector were identified as potential sources of fish abundance and harvest information. Formal freshwater recreational angling in South Africa is a highly organised, multi-faceted activity which is based primarily on angling for non-native species, particularly common carp Cyprinus carpio and largemouth bass Micropterus salmoides. Bank anglers constituted the largest number of formal participants (5 309 anglers affiliated to formal angling organisations) followed by bass anglers (1 184 anglers affiliated to formal angling organisations). The highly structured nature of organised recreational angling and dominant utilisation of inland fisheries resources by this sector illustrated not only the vested interest of anglers in the management and development of inland fisheries but also the role that anglers may play in future decision-making and monitoring through the dissemination of catch data from organised angling events. Generalised linear models (GLMs) and generalised additive models (GAMs) were used to standardise CPUE estimates from bass- and bank angling catch records, which provided the most suitable data, and to determine environmental variables which most influenced capture probabilities and CPUE. Capture probabilities and CPUE for bass were influenced primarily by altitude and conductivity and multiple regression analysis revealed that predictive models incorporating altitude, conductivity, surface area and capacity explained significant (p<0.05) amounts of variability in CPUE (53%), probability of capture (49%) and probability of limit bag (74%). Bank angling CPUE was influenced by conductivity, surface area and rainfall although an insignificant (p>0.05) amount of variability (63%) was explained by a predictive model incorporating these variables as investigations were constrained by small sample sizes and aggregated catch information. Scientific survey data provided multi-species information and highlighted the high proportion of non-native fish species in Eastern Cape impoundments. Gillnet catches were influenced primarily by species composition and were less subject to fluctuations induced by environmental factors. Overall standardised gillnet CPUE was influenced by surface area, conductivity and age of impoundment. Although the model fit was not significant at the p<0.05 level, 23% of the variability in the data was explained by a predictive model incorporating these variables. The presence of species which could be effectively targeted by gillnets was hypothesised to represent the most important factor influencing catch rates. Investigation of factors influencing CPUE in impoundments dominated by Clarias gariepinus and native cyprinids indicated that warmer, younger impoundments and smaller, colder impoundments produced higher catches of C. gariepinus and native cyprinids respectively. A predictive model for C. gariepinus abundance explained a significant amount of variability (77%) in CPUE although the small sample size of impoundments suggests that predictions from this model may not be robust. CPUE of native cyprinids was influenced primarily by the presence of Labeo umbratus and constrained by small sample size of impoundments and the model did not adequately explain the variability in the data (r² = 0.31, p>0.05). These results indicate that angling catch- and scientific survey data can be useful in providing predictions of fish abundance that are biologically realistic. However, more data over a greater spatial scale would allow for more robust predictions of catch rates. This could be achieved through increased monitoring of existing resource users, the creation of a centralised database for catch records from angling competitions, and increased scientific surveys of South African impoundments conducted by a dedicated governmental function.
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Wiium, Vilhjálmur Hansson. "Discarding of fish and fisheries management, an economic perspective." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ61695.pdf.
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Stewart, Heather Jackson. "UK sea fisheries policy-making since 1945." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31414.
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This is a study of approaches to fisheries management in the United Kingdom (UK) between 1945 and 1996. It examines the choices and incentives faced by UK Governments when designing policy instruments to deliver international commitments to sustainable fishing. The failure of international agreements to sustainably manage fisheries resources is often attributed to international institutions, the politicization of negotiations and their distributive outcomes. This thesis makes an original contribution by arguing that the success of international agreements was also dependent upon local negotiations that shaped the design of national delivery mechanisms. The central research question concerns the role and influence of local interests in delivering global economic and environmental agendas and how national governments accommodate local tensions within this process. A sustained content analysis of UK Government archives is used to argue that local political and sectional industry interests had a significant bearing on the development of UK fisheries policy and the design of domestic delivery mechanisms. The exception was UK policy on the international distribution of fisheries resources at the United Nations Law of the Sea Conferences (1958, 1960 and 1973-82). Economic considerations drove early environmental policy with sectional fishing industry interests of secondary importance to the potential economic benefits associated with the more valuable energy resources. In then seeking to implement controls on fishing activity, this thesis argues that UK fisheries management mechanisms were designed to compensate for tension between global commitments mandating a reduction in fishing effort and the local fleets and communities that had to bear the costs of industry contraction. This created a policy-making environment in which social and political motivations continually trumped the application of economic and scientific advice. This advice advocated a contraction in the size of the fleet which had become necessary as technical change and falling stocks resulted in overcapacity. The use of fisheries policy as a political tool to ease local tensions incentivised policy choices that directly contributed to the UK's failure to reduce fishing pressure and deliver international commitments. This thesis demonstrates the importance of local negotiations and interests in the construction of national and international approaches to environmental and natural resources problems.
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Medina, Miles D. "Effect of Aquafeed on Productivity of Red Amaranth and on Water Quality under Aquaponic Cultivation." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1206.
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Aquaponics, the integrated production of fish and hydroponic crops in a recirculating system, is an intensive cultivation method in which metabolic fish wastes fertilize plants. This study compares the effects of two aquafeeds on Red amaranth (Amaranthus tricolor) productivity and on water quality under cultivation of Blue tilapia (Oreochromis aureus), with three aquaponic units (n=3) per treatment over a 60-day trial. The fishmeal-based control feed contains higher crude protein (40%) and phosphorus (1.12%) than the plant-based alternative feed (32% and 0.40%). The alternative feed resulted in a significantly higher amaranth crop yield (p
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Elefante, Ilaria <1988>. "Sustainable Perspectives in Mediterranean Fisheries: European Policies." Master's Degree Thesis, Università Ca' Foscari Venezia, 2013. http://hdl.handle.net/10579/2465.
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La mia tesi verterà sulle politche della comunità europea relative alla pesca e alla protezione dell'ambiente marino, con una particolare attenzione per l'area mediterranea. La tesi si dividerà in tre capitoli principali i cui argomenti saranno una presentazione generale dell'area mediterranea, la legislazione riguardante le attività di pesca e la protezione dell'ambiente marino ed infine la descrizione di due casi di studio diversi ma complementari, l'italia e il marocco, che si differenziano sia dal punto di vista geografico che politico.