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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Utilização de habitat e movimentos migratórios do Agulhão Negro (Makaira nigricans) no oceano Atlântico Sul

CRESPO NETO, Osman 27 June 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-02-16T13:34:08Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) OsmanCrespo_Dissertação_PPGO.pdf: 2113471 bytes, checksum: adc84d0652f9664545cb0bdac4dae2cf (MD5) / Made available in DSpace on 2017-02-16T13:34:08Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) OsmanCrespo_Dissertação_PPGO.pdf: 2113471 bytes, checksum: adc84d0652f9664545cb0bdac4dae2cf (MD5) Previous issue date: 2016-06-27 / CAPES / O agulhão negro (Makaira nigricans) é uma espécie dentre os grandes peixes pelágicos que compõe o topo da teia trófica marinha, sendo sua preservação importante para a manutenção da dinâmica populacional desses ecossistemas. Esta espécie é uma das mais procuradas pela pesca esportiva no mundo, sendo, porém, alvo de sobrepesca devido sua captura frequente como fauna acompanhante na pesca de espinhel pelágico no oceano Atlântico. O objetivo do presente trabalho de pesquisa foi compreender os movimentos migratórios, a influência de fatores ambientais em padrões de movimento e utilização de habitat pelos agulhões-negro no oceano Atlântico Sul e como essa espécie interage com o aparelho de pesca. Para o levantamento de dados sobre a utilização de habitat foram utilizadas marcas PSATs (pop-up satellite archival tags) para monitorar o comportamento do animal registrando um fluxo quase contínuo de parâmetros ambientais especificados (temperatura, pressão [profundidade] e luminosidade), onde os dados são arquivados e transmitem a informação via satélite após se desconectarem do animal. Além disso, foram também analisadas as profundidades de atuação dos anzóis do espinhel na pesca comercial de atuns e afins no Atlântico Sul, para melhor compreender quanto o esforço de pesca atualmente empregado se sobrepõe ao habitat utilizado pelos agulhões. O deslocamento horizontal durante o período de marcação variou de 374 a 1.838 km. Os resultados mostraram que os indivíduos maiores (>195 cm), considerados adultos, apresentaram deslocamentos direcionais segundo a estatística circular aplicada, enquanto que indivíduos juvenis ou menores (<195 cm) apresentaram deslocamentos considerados loopings ou sem direcionamento definido. Os dados de tempo em profundidade nos mostraram que a os indivíduos passam a maior porcentagem do tempo em águas superficiais acima dos 20m durante os períodos noturno e diurno. Os agulhões negros permaneceram a maioria do tempo dentro de uma curta faixa de temperatura, com uma média de 57% do tempo em temperaturas entre 26º e 28ºC. Os resultados quanto a sobreposição de habitat à espinhéis pelágicos nos mostrou uma relação de 59% da área rastreada sobreposta às armadilhas de pesca. A média de profundidade dos anzóis registrada foi de 49 m, sendo 90% da distribuição de profundidade dos anzóis entre 3271m. Essa distribuição vertical quando sobreposta ao padrão de utilização vertical do habitat pelos agulhões, revelou uma sobreposição que varia entre 11% e 35% durante o período diurno e 21% e 34% durante a noite. Os resultados obtidos na presente pesquisa são relevantes para uma melhor compreensão da biologia e ecologia dos agulhões negros no oceano Atlântico Sul, compondo um importante conhecimento sobre o comportamento da espécie e auxiliando para tomada de decisões e medidas de manejo e conservação da espécie a nível internacional. / Blue marlin (Makaira nigricans) is a species among great pelagic fishes that occupy the top of marine food web, being its conservation important to the maintenance of ecosystem population dynamics. Atlantic blue marlin is one of the favorite species targeted by recreational fishing in the Atlantic Ocean, however being overexploited because of its frequent capture as bycatch by commercial pelagic longline fishery. The main goal of this study was to understand migratory movement and the influence of environmental factors in movement patterns and habitat utilization by blue marlins in the South Atlantic Ocean and how this species interacts with pelagic longline gear. Pop up archival tags (PSATs) were used to collect habitat utilization data monitoring animal behavior through continuous records of specified environmental parameters (temperature, pressure [depth] and luminosity), transmitting such reports via satellite after pop-off. Furthermore, was also analyzed longline gears hook depths from commercial fisheries in South Atlantic to better understand how this fishing effort overlap to marlins habitat utilization. PSATs were programmed to record depth, temperature, and light intensity for a period of 180 days until release. The horizontal net displacement for all blue marlins ranged from 374 to 1.838 km. Results presented that larger individuals (>196 cm), considered adults, achieved directional movements according to circular statistics applied, while shorter individuals (<195 cm) presented displacement as looping or nondirectional. Time-at-depth histograms of blue marlin habitat utilization show that most individuals across all areas spent the majority of their time in shallow waters, above 20m, both during the day and night periods. Blue marlins spent most of their time within a relatively narrow temperature range, staying an average of 57% of their time in temperatures between 26° and 28°C. Overall, blue marlins had approximately 59% of their tracked range overlapped by the longline fishing gear. The average hook depth across all areas was 49 m with 90% percentile depth distribution of the hooks depth between 32-71 m. When this distribution was overlapped with the species vertical habitat utilization, the overlap ranged between 11 and 35% during daytime and 21 and 34% during nighttime. The results achieved in this study are relevant to better understand the biology and ecology of Atlantic blue marlins, composing an important knowledge about species behavior, which reduces current uncertainties about its biology and help to making decisions and take international conservation and management measures to the species.
2

Rybářské obhospodařování Slapské údolní nádrže / Angling Management in the Slapy Riverine Lake

Babický, Jan January 2018 (has links)
The master's thesis focuses on Slapy valley reservoir which is first described as a suitable location for fishing and recreation. Special attention is also paid to its history. The main body of the thesis features the enumeration and characteristics of individual fish species which occur in the reservoir. Furthermore, the thesis deals with the evaluation of the fishing management of the reservoir from 1962 to 2016 considering fish stock and catches of individual species. Factors influencing the development and dynamics of the fish stock are also evaluated. The summary management of Slapy valley reservoir is analyzed in terms of fish stocking and fishing yields. In addition, the population dynamics trends of predatory and non-predatory fish species are analyzed on the basis of fishing catches. In the conclusion, the current condition of the fish stock is evaluated and some minor recommendations for optimizing the fishing management of the reservoir are proposed. KEYWORDS: fish, Slapy, valley reservoir, sport fishing, catch, fish stock, fishing management
3

ASPECTOS SOCIAIS, ECONÔMICOS E AMBIENTAIS DA PESCA ARTESANAL EM LUIS ALVES DO ARAGUAIA-GOIÁS. / SOCIAL, ECONOMIC AND ENVIRONMENTAL ASPECTS OF ARTISANAL FISHING ACTIVITY IN LUIS ALVES DO ARAGUAIA-GOIÁS.

Miguel, Cristianne Borges 04 May 2012 (has links)
Made available in DSpace on 2016-08-10T10:31:02Z (GMT). No. of bitstreams: 1 CRISTIANNE BORGES MIGUEL.pdf: 2717815 bytes, checksum: 61dc63f7200917edfad73f15436c851b (MD5) Previous issue date: 2012-05-04 / The artisanal fishing activity practiced in the village of Luiz Alves is essential for a population of about 300 fishermen directly linked to the practice of fishing, and regional tourism. Due to legal restrictions quota and commerce fishing in the state of Goiás, the fisherman needs to develop new ways to improve family income using the resources of the river. Thus, this study aimed to understand the dynamics of the fishing activity conducted by fishermen from the town of Luiz Alves, via a socio-economic and environmental systematic profile survey of the fisherman and live bait fishing practices in order to subsidize managements and planning proposals, and contribute to a sustainable management of the natural resources of the river. We interviewed 88 fishermen residing in the town of Luiz Alves who were willing to participate. The results demonstrate the social economic and environmental importance of fishing not only as a source of protein in nourishment, but also as a way of interaction between fishing activities and tourism, as an employment alternative, and as a source of income and survival throughout the year for the fishermen of the region. In addition to the subsistence fishing, the fishermen also consider the activity of Fishing Guide as a professional one, being it a means to contribute to their annual income. During this study conflicts were observed between the fishermen and the environmental legislation, such as places of fishing, fishing equipment to get bait (fishing net), catching and commercialization of protected fish. A consensus is observed among the fishermen that the maintenance of the ecosystem integrity of the Araguaia River is fundamental to any initiative aimed at its exploration. The fisherman has the perception that the development of fishery should be conducted in substantives bases, such as: the interest shown in promoting joint actions with managing organizations; the development of legal work experience; encouragement of sport fishing; preservation breeding, that is, producing bait to feed the rivers if necessary so that it might meet the demands of sport fishermen, reducing the pressure of fish stocks beyond the adoption of zero quota for transport. The results suggest that conserving fish stocks and developing sustainable use of the resource should not be an assignment just for the fishermen, but a partnership with the society should be developed, involving the community, governmental and non-governmental organizations and other actors in order to promote and execute a Management Plan to the Area of Environmental Preservation of the Araguaia River Meanders. / A pesca artesanal praticada no povoado de Luis Alves é uma atividade essencial para uma população com cerca de 300 pescadores ligados diretamente à prática pesqueira e ao turismo regional. Devido a restrições legais de cota e comércio na pesca em Goiás, o pescador tem a necessidade de desenvolver novos meios de agregar valor à renda familiar utilizando os recursos do rio. Assim, o objetivo deste trabalho é compreender a dinâmica da atividade pesqueira exercida pelos pescadores artesanais do Povoado de Luis Alves do Araguaia, através do levantamento sistemático do perfil sócio-econômico e ambiental do pescador artesanal e da prática pesqueira de iscas vivas, a fim de subsidiar propostas de manejos e ordenamento, e contribuir para a gestão sustentável dos recursos naturais do rio. Foram entrevistados 88 pescadores artesanais residentes no povoado de Luiz Alves que se dispuseram a participar da pesquisa. Os resultados demonstram a importância social, econômica e ambiental da pesca artesanal como fonte de proteína na alimentação, interação entre as atividades de pesca e turismo, alternativa de emprego, renda e sobrevivência durante todo o ano para os pescadores artesanais da região. Os pescadores, além da pesca de subsistência, também praticam e consideram a atividade de Guia de Pesca como referência de profissão, sendo que esta contribui com a maior parte da renda anual. Foram observados conflitos ao longo desse estudo entre os pescadores e a legislação ambiental vigente, tais como: locais de captura do pescado, petrechos de pesca para coleta de iscas (tarrafa), captura de peixes protegidos e comercialização do pescado. Há consenso entre os pescadores de que a manutenção da integridade do ecossistema do rio Araguaia é fundamental para qualquer tipo de iniciativa que vise a sua exploração. O pescador tem a percepção que o desenvolvimento da pesca deve ser realizado em bases sustentáveis, a exemplo, o interesse demonstrado em promover ações conjuntas com os órgãos gestores; trabalhar de forma legalizada; incentivar a pesca esportiva; preservar os reprodutores, produzir iscas para povoamento dos rios se necessário e atender a demanda dos pescadores esportivos, diminuindo a pressão do estoque pesqueiro além da adoção de cota zero para transporte. Os resultados sugerem que a conservação dos estoques pesqueiros e o uso sustentado do recurso não deve ser uma atribuição apenas dos pescadores, mas realizada de modo compartilhado com da sociedade de modo geral, envolvendo a comunidade, os setores privados, organizações governamentais e não governamentais e demais atores envolvidos a fim de promover a execução de um Plano de Gestão para a Área de Preservação Ambiental Meandros do Rio Araguaia.
4

Využití produkčních rybníků pro sportovní rybolov na Třeboňsku a Novohradsku / Usage of production ponds for sport fishing in area of Třeboň and Nové Hrady

VIDRMAN, Jan January 2008 (has links)
After a year 1989 opened new possibilities for sport fishing. The biggest change in this direction is the possibility of fishing in private fishing grounds. Fishing firms and the other private subjects started to derive benefit from this kind of fishing. This phenomenon is caused by increasing of the fishing pressure on wild waters and higher buying power of the population and its willingnes to spend more money for quality leisure time.Because most of these fishing grounds belong to commercial producers of market fish and sport fishing is realized as a form of economic mining fish on rod as a payed service. This fact causes different way of organisation and different rules of sport fishing.
5

L'évolution de la pêche en Mauritanie depuis l'indépendance à nos jours (1960-2009) / Fishing growth in Mauritania from the independance to nowadays (1960-2009)

Ould Mohamed, Sidi Mohamed 08 October 2010 (has links)
Une ZEE de près de 230000 km², avec un plateau continental d’environ 39000 km², balayée par l’intense upwelling présent pratiquement toute l’année dans cette zone de l’Atlantique centre est, expliquent la richesse biologique des eaux mauritaniennes et leur potentiel élevé en ressources halieutiques, avec des espèces diversifiées et de valeur marchande élevée.Plusieurs décennies d’efforts s’appuyant sur des politiques centrées sur la conservation des ressources halieutiques et l’intégration de la pêche à l’économie nationale, ont permis au pays d’impulser le développement d’un secteur national dynamique de pêche.Le développement des institutions nationales et de la réglementation a permis d’asseoir la souveraineté de l’Etat sur la ZEE, de codifier le droit régalien de l’Etat sur les ressources halieutiques, de déterminer les mécanismes d’allocation des droits de pêche et leurs supports physiques, et d’organiser les structures chargées de la mise en œuvre des ces institutions. Avec une contribution moyenne au cours des dernières décennies, de 4-10% du PIB, de 20-30% des recettes budgétaires, les recettes en devises générées par l’exportation des produits et les redevances de pêche versées par les armements étrangers, qui constituent un soutien important au budget national, la pêche mauritanienne joue, depuis quelques décennies, un rôle clef dans la réalisation des objectifs des politiques économiques du pays.La Mauritanie a toujours été un pays habité en majorité par des nomades qui ne connaissaient pas la mer auparavant, à l’exception de la tribu Imraguen qui pratiquait la pêche traditionnelle depuis des générations. Il est aujourd’hui tourné vers la mer par nécessité et commence à se rendre compte de ses ressources aussi bien bénéfiques pour sa population que pour son développement économique. Cependant, l’avenir du secteur de la pêche sera surtout dessiné avec la mise en place des plans d’aménagement efficaces, qui vont constituer le cadre de gestion du secteur de la pêche pour les prochaines années. / An EEZ of nearly 230,000 square kilometers, with a continental shelf of about 39000 km ², swept by the intense upwelling that is present during almost the whole year in this area of the East Middle Atlantic, explain the biological richness of Mauritanian waters and their high potential in fish resources, with diverse species and high market value. Several decades of effort based on policies that focus on the conservation of fishery resources and the integration of fisheries to national economy, have enabled the country to boost the development of a dynamic national sector of fishery. The development of national institutions and the regulation has helped to underpin the State's sovereignty over the EEZ, to codify the sovereign right of the State on fisheries resources, to determine the mechanisms for allocating fishing rights and their physical media, and organize the structures responsible for the implementation of these institutions. With an average contribution over the past decades, over 4-10% of GDP, 20-30% of fiscal revenue, foreign exchange earnings generated by exports of goods and royalties paid by the fishing foreign arms, which constitute an important support to the national budget, the Mauritanian fishing plays in recent decades, a key role in achieving the objectives of economic policy of the country. Mauritania has always been a country inhabited mostly by nomads, who does not know the sea, except the tribe Imraguen who practice the traditional fishery for generations. It is now facing the sea through necessity and begins to realize its resources as beneficial for its people as its economic development. However, the future of fisheries will be especially designed with the introduction of effective management plans, which will provide the framework for management of fisheries in the coming years.
6

Podnikatelský záměr pro založení firmy TOP BAITS / Business Plan for Establishment of the Company TOP BAITS

Pásler, Tomáš January 2014 (has links)
This Master´s thesis deals with the business plan for establishment of a corporation TOP Baits. It is in the business of manufacturing and selling baits for carp fishing. The thesis is divided into several chapters are devoted to theoretical knowledge ofbusiness analysis, general and business environment and its own proposals for solutions.
7

Evaluating supervised machine learning algorithms to predict recreational fishing success : A multiple species, multiple algorithms approach / Utvärdering av övervakade maskininlärningsalgoritmer för att förutsäga framgång inom sportfiske

Wikström, Johan January 2015 (has links)
This report examines three different machine learning algorithms and their effectiveness for predicting recreational fishing success. Recreational fishing is a huge pastime but reliable methods of predicting fishing success have largely been missing. This report compares random forest, linear regression and multilayer perceptron to a reasonable baseline model for predicting fishing success. Fishing success is defined as the expected weight of the fish caught. Previous reports have mainly focused on commercial fishing or limited the research to examining the impact of a single variable. In this exploratory study, multiple attributes and multiple algorithms are examined to determine if supervised machine learning is a viable tool to predict recreational fishing success. Recreational fishing success can potentially be predicted by a large number of attributes, which may be different for different species. In this report, data is fetched from multiple sources and combined into a unified data format. The primary source of data is a database from the fishing app FishBrain, containing data of over 250000 logged catches. Another is the World Weather Online API which supplies weather data. The report focuses on the four most common species in the database, largemouth bass, Micropterus salmoides, northern pike, Esox lucius, rainbow trout, Oncorhynchus mykiss and European perch, Perca fluviatilis with a focus on largemouth bass since it has the most data available. Algorithms are evaluated using the Weka data mining software. Hyperparameters are found using cross-validation and some data is used as a test set to validate the results after cross-validation. Results are measured as the error compared to a baseline algorithm. Random forest is the most effective algorithm in the experiments, reducing error compared to the baseline for all the examined fish species. It is also found that no single variable affects the chosen metric of fishing success much, but rather a combination of most of the examined variables is needed to give optimal predictions. In conclusion, the random forest algorithm can be used to predict fishing success across multiple species. It performs significantly better than linear regression, multilayer perceptron and the baseline on crossvalidation and on the testing set. / I denna rapport evalueras tre olika maskininlärningsalgoritmer och deras effektivitet för att förutsäga framgång inom sportfiske. Sport- fiske är en mycket populär hobby, men pålitliga metoder att förutsäga framgångsrikt sportfiske saknas. Denna rapport jämför random forest, linjär regression och flerlagers neurala nätverk mot en rimlig baselinealgorithm för att förutsäga framgång inom sportfiske. Framgång defineras som fiskens förväntade vikt i kg. Tidigare undersökningar har huvudsakligen fokuserat på kommersiellt fiske eller begränsat undersökningen till påverkan av en enskild variabel. I denna studie undersöks flera attribut och algoritmer för att avgöra om övervakad maskininlärning är ett användbart verktyg för att förutsäga framgång inom sportfiske. Framgång inom sportfiske kan potentiellt påverkas av ett stort antal attribut som kan vara olika för olika arter. I denna studie hämtas data från ett flertal källor som kombineras i ett unifierat dataformat. Den primära datakällan är en databas tillhörande sportfiskeappen FishBrain som innehåller över 250000 loggade fångster. En annan källa är World Weather Online:s API som bidrar med väderdata. Rapporten fokuserar på de fyra vanligaste arterna i databasen, largemouth bass, Micropterus salmoides, gädda, Esox lucius, regnbågsöring, Oncorhynchus mykiss och europeisk abborre, Perca fluviatilis med ett särskilt fokus på largemouth bass eftersom den har mest data tillgängligt. Algoritmerna evalueras med hjälp av data mining-verktyget Weka. Hyperparametrar bestäms med hjälp av korsvalidering och en delmängd av datan separeras och används för att validera resultaten efter korsvalidering. Resultaten mäts relativt en baseline-algoritm. Random forest är den mest effektiva algoritmen i experimenten och reducerar felet jämfört med baseline-algoritmen för alla undersökta fiskarter. Inget enskilt attribut påverkar slutresultatet mycket utan det behövs en kombination av flera attribut för att ge optimala prediktioner. Slutsatsen blir att random forest kan användas för att förutsäga framgång inom sportfiske för flera olika fiskarter. Den presterar signifikant bättre än linjär regression, flerlagers neuralt nätverk och baselinealgoritmen på korsvalidering och på testdelmängden.

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