The prevalence of hypoxia in aquatic systems has increased in recent decades and climate change is expected to worsen the extent and severity of hypoxic phenomena worldwide. Moreover, aquatic hypoxia has produced adverse ecological consequences and stimulated research interest within the Laurentian Great Lakes. The physiological stress imposed by hypoxia reduces habitat quality for most aquatic biota and causes changes in patterns of resource use and food web dynamics. We conducted a review of the primary literature to identify trends in prevalence of Great Lakes hypoxia research and broadly classify the unique hypoxic conditions afflicting Great Lakes ecosystems. We found that the majority of research effort toward Great Lakes hypoxia is focused on the Lake Erie central basin. Our review further revealed that this does not characterize the breadth of hypoxic phenomena that occur throughout the Great Lakes region. We then utilized a long-term monitoring dataset provided by the U.S. Environmental Protection Agency Great Lakes National Program Office to quantify the impact of Lake Erie central basin hypoxia on habitat quality of several fish species. We found that bioenergetics-based growth-rate potential models have a potential application as the framework for the development of biological endpoints that measure the effects of hypoxia on aquatic biota. Finally, we utilized stable isotope analysis to look for broad spatial and temporal trends in resource utilization within distinct regions of the Lake Erie central basin, with hypoxia and large-scale hydrodynamic patterns serving as potential driving patterns for spatial differences.

No description available.

The oceans around the world have been heavily impacted by overfishing due to very intensive commercial fishing in recent times. A large number of fish stocks have already been fully exploited. Vessel Monitoring System has been put in place to regulate fishing vessels and enforce sustainable fisheries management. Data coming from such systems can be used for the detection of illegal, unregulated, and unreported fishing. In this thesis, we present various machine learning models for the classification of fishing trip trajectories. To train these models, we develop a trajectory segmentation algorithm to create trip trajectories out of raw data and design a graphical user interface for labeling the trip trajectories into fishing and non-fishing. We also examine the impact of the temporal resolution of the data. In conclusion, the CNN-Transformer network performed the best on the binary classification of two different fishing vessel types. During the project, we realized that segmentation of real trajectory data into trips poses many problems and presents the biggest obstacle. The experiment on the varying temporal resolution of the data showed that having a higher temporal resolution gives better modeling results but only to a certain point. / Haven runt om i världen har drabbats hårt av överfiske på grund av ett mycket intensivt kommersiellt fiske på senare tid. Ett stort antal fiskbestånd har redan utnyttjats fullt ut. Fartygsövervakningssystem har införts för att reglera fiskefartyg och upprätthålla hållbar fiskeförvaltning. Data som kommer från sådana system kan användas för att upptäcka olagligt, oreglerat och orapporterat fiske. I detta examensarbete presenterar vi olika maskininlärningsmodeller för klassificering av fisketursbanor. För att träna dessa modeller utvecklar vi en segmenteringsalgoritm för att skapa turbanor av rådata och designa ett grafiskt användargränssnitt för att märka resbanorna till fiske och icke-fiske. Vi undersöker också effekten av den tidsmässiga upplösningen av datan. Sammanfattningsvis presterade CNN-Transformer-nätverket bäst i den binära klassificeringen av två olika fiskefartygstyper. Under projektet insåg vi att segmentering av verkliga bandata till resor utgör många problem och utgör det största hindret. Experimentet på den varierande tidsupplösningen av data visade att en högre tidsupplösning ger bättre modelleringsresultat men bara till en viss punkt.

No description available.

1982年《聯合國海洋法公約》確立了專屬經濟區的制度後，公海成為海洋生物資源養護與管理的一大缺口，特別是在養護與管理跨界及高度洄游魚群上產生防護的漏洞。1995年國際間通過《聯合國跨界與高度洄游魚類協定》，旨在履行《聯合國海洋法公約》關於養護跨界與高度洄游魚群之規定，並進一步訂立更完善之規範，特別是協定重視各區域性漁業組織之功能，期能透過該些組織，更有效率地管理並養護各區域之跨界與高度洄游魚群。因此，《聯合國海洋法公約》、1995年協定與區域性漁業組織相互間透過法律規範，從架構、實踐與實際執行這三方面試圖形塑一個較為嚴謹及嚴密的網絡。 2004年中西太平洋漁業委員會（WCPFC）成立。協定與委員會透過登臨與檢查的方式，以養護與管理在公海海域之跨界與洄游魚群。然公海自由及公海上由船旗國管轄乃習慣國際法，而為在保育海洋生物資源，在公海上採取相互登臨與檢查為國際海洋法發展之趨勢。由於登臨與檢查乃涉及一國之主權問題，台灣因於國際上之特殊地位，在WCPFC中之登臨與檢查權便為一值得探討之議題。 《WCPFC登檢程序》規定《WCPFC公約》之締約方有相互登臨檢查之權利與義務，而WCPFC之會員有被登檢之義務。由於台灣乃以漁業實體之身份加入，成為WCPFC之會員，並非《WCPFC公約》之締約方，因此台灣是否有登檢其他會員船舶之權利便為我方關切之議題。筆者透過對1995年協定、《WCPFC公約》，以及《WCPFC登檢程序》之分析，認為台灣倘與其他會員或《WCPFC公約》締約方締結登檢協議，則台灣與協議締約方間當可享有《WCPFC登檢程序》中規定之完整的登檢權利與義務，而不受僅為「會員」身份所造成之模糊地位所限制。 / As the 1982 LOS Convention establishes the concept of Exclusive Economic Zone, the high seas has not only become the rest areas without authorities’ jurisdiction, but also been a breach of the conservation and management of living recourses, especially in aspect of the conservation and management of straddling and highly migratory stocks. In 1995, Straddling Stocks Agreement was approved, in which the main purpose is to enforce the principles of LOS Convention relating to the conservation and management of straddling and highly migratory stocks. Straddling Stocks Agreement respects the functions of the regional fishing organizations and expects it to manage and conserve straddling and highly migratory stocks more efficiently in each region. Consequently, through making stipulations, the LOS Convention, 1995 Agreement, and regional fishing organizations attempt to build up a strict network of framework, implementation, and enforcement. In 2004, WCPFC Commission was founded. Through boarding and inspection, 1995 Agreement and WCPFC Commission conserve and manage the straddling and highly migratory stocks. Although the high-seas freedoms and flag State jurisdiction are the parts of customary international law, it is the trend in development of international law to adopt boarding and inspection in high seas for conserving living resources in ocean. Due to boarding and inspection concerning the sovereignty, as the special status in international society, Taiwan’s boarding and inspection rights in WCPFC Commission become a disputed issue. WCPFC Boarding and Inspection Procedures imply that the Contracting Parties of WCPFC Convention have rights and obligations to board and inspect each other’s ships, but the members of WCPFC only have the obligation of being boarded and inspected. Since Taiwan, as the fishing entity, participated in WCPFC as the Member rather than the Contracting Parties. As a result, whether Taiwan possessing any rights to board and inspect other members’ ships is concerned by Taiwan’s authority. By analyzing 1995 Agreement, WCPFC Convention, and WCPFC Boarding and Inspection Procedures, the author concludes that if Taiwan has the agreements relating to boarding and inspection with other Members or Contracting Parties, Taiwan would absolutely possess the full rights and obligations, which the WCPFC Boarding and Inspection Procedures stipulate, without constrained by its ambiguous status caused by the role of Member.

Cette thèse a pour thème central l'étude de deux problèmes soulevés dans les pêcheries modernes, la dégradation des habitats et le manque d'informations, qui comptent parmi les causes les importantes de la surexploitation des ressources halieutiques. Les deux premiers chapitres sont consacrés à l'examen du problème de la dégradation des habitats marins liée notamment aux activités de pêche destructrices. Le modèle de Gordon-Schaefer est prolongé afin de tenir compte de l'impact négatif de la pêche sur les habitats. Les conséquences pour la gestion sont analysées et l'importance de la prise en compte des habitats dans le développement des programmes de gestion des ressources halieutiques est mise en évidence. Le modèle élaboré est ensuite utilisé pour évaluer les bénéfices économiques des récifs artificiels, un outil de gestion auquel font de plus en plus appel les gestionnaires des pêcheries artisanales pour répondre à la dégradation des habitats. Enfin, dans le troisième chapitre, le rôle de l'information pour une pêche durable est examiné lorsque la ressource est en accès libre. Si, dans les deux premiers chapitres, il est supposé que les informations complètes sont disponibles pour l'élaboration des recommandations de gestion, dans la dernière étude, la décision concernant l'exploitation des ressources halieutiques est prise dans un contexte où aucune information sur la ressource n'est accessible. Cette décision est prise individuellement par chaque pêcheur qui opère dans la pêcherie. En développant un modèle multi-agents, nous montrons l'impact de l'apprentissage des pêcheurs sur la dynamique globale du système halieutique. / This thesis focuses on two main problems posed in contemporary fisheries: habitat degradation and lack of information. They count among the most important causes of the overexploitation of marine resources. The first two chapters aim at examining the habitat degradation that is linked to destructive fishing activities. The Gordon-Schaefer model is extended to take account of the negative impact of fishing on the habitats. The consequences for fisheries management are analyzed and the importance of taking into account habitats in the development of fisheries management programs is highlighted. Then the extended model is used to evaluate the economic benefits of artificial reefs, a management tool to which frequently resort the managers of small-scale fisheries to mitigate the effects of habitat degradation. Finally, in the third chapter the role of information for sustainable fisheries is examined under open access. If in the first two chapters it is assumed that there is complete information, in the last study this assumption is relaxed - no information on the resource is known. The decision concerning the exploitation of marine resources is made individually by each fisherman that operates in the fishery. By developing an agent-based model, we show the impact of individual learning on the global dynamics of the system.

Made available in DSpace on 2015-03-04T18:51:06Z (GMT). No. of bitstreams: 1 tese Eliane Coutinho.pdf: 2566919 bytes, checksum: 6cf0fc650b3992a20e2109fea4e81a82 (MD5) Previous issue date: 2009-11-28 / Pirarucu ( Arapaima gigas) has been one of the most important economic resources among all the fish species of the Brazilian Amazon for more than three centuries. The introduction of modern technologies of exploitation brought serious threats to the preservation of this species. Adequate management strategies have to be urgently introduced in order to prevent extinction. The aim of this work is to present a mathematical model for the pirarucu population dynamics considering the species peculiarities and the different fishing rates to supply subsides for its conservation. In order to differentiate its respective role in breeding, the population is divided into two groups: female and male. The parameters introduced in this paper are derived from limited but reliable field data collected at the Mamirauá Sustainable Development Reserve (MSDR) in the Brazilian Amazonian Region. Complementary parameters are estimated from biological considerations and commonsense. / O Pirarucu (Arapaima gigas ) tem sido dos mais importante recursos econômicos entre todas as espécies de peixe da Amazônia Brasileira por mais de três séculos. A introdução de tecnologias modernas de exploração trouxe graves ameaças à preservação desta espécie. Estratégias de manejos adequados devem ser urgentemente introduzidas, a fim de evitar extinção. O objetivo deste trabalho é apresentar um modelo matemático para a dinâmica populacional do pirarucu considerando peculiaridades da espécie e as diferentes taxas de pesca de modo a fornecer subsídios para a sua conservação. A fim de diferenciar seus respectivos papéis na reprodução, a população está dividida em dois grupos: machos e fêmeas. Os parâmetros assumidos no presente trabalho são parcialmente derivados de dados de campo limitados, mas seguros da Reserva de Desenvolvimento Sustentável de Mamirauá na região Amazônica Brasileira . Alguns outros parâmetros são estimados a partir de considerações biológicas.

Species conservation is typically founded upon a range of management strategies, which integrate both biological and socioeconomic data. In this thesis, population genetics, acoustic telemetry, spawning aggregation surveys and stakeholder assessments were used to address key knowledge gaps limiting effective conservation management for critically endangered Nassau grouper (Epinephelus striatus) stocks in The Bahamas. A panel of polymorphic microsatellite markers was optimised to assess the genetic population dynamics of more than 400 Nassau grouper sampled throughout the country. Microsatellite data indicate that contemporary Nassau grouper populations in The Bahamas are predominantly genetically diverse and weakly differentiated, but lack geographic population structure. Assessments of changes in effective population size (Ne) show substantive reductions in Ne within The Bahamas compared to historic values that are likely due to natural disturbances. Evidence for recent bottlenecks occurring in three islands as well as an active spawning site, along with higher inbreeding coefficients in two islands were also found, and can be attributed to more recent anthropogenic activities. Collapse of a historically important Nassau grouper fish spawning aggregation (FSA) was supported by both acoustic telemetry and spawning aggregation survey dives. Restriction-site-associated DNA sequencing (RAD-seq) of 94 Nassau grouper was used to explore intraspecific population dynamics, loci under selection and patterns of gene flow in The Bahamas. Genomic assessments of diversity were in accord with microsatellite data and examinations of gene flow support higher levels of connectivity in The Bahamas than was previously suggested. The increased resolution gained from assessments of genomic data support intraspecific population structuring that may be driven by differences in gene flow and putative loci under divergent selection. Telemetry data were successfully used to identify the origins of spawning adults, and support demographic connectivity through migrations between an active FSA in the central Bahamas and home reef habitats within the Exumas and a no-take marine protected area. Stakeholder assessments highlight the complexities of fisheries management within The Bahamas, with key stakeholders often exhibiting conflicting opinions regarding the status of Nassau grouper and the efficacy of management options. However, these groups mutually agree upon the need to better manage remaining Nassau grouper stocks within The Bahamas through science-grounded policies. Synthesis of these studies along with a review of fisheries governance in The Bahamas was used to develop a comprehensive national management plan for Nassau grouper to facilitate better conservation for remaining populations of this ecologically important marine species.

Em Ubatuba (SP), a pesca apresenta grande importância sócio-econômica e requer, como em outros locais, um manejo adequado. Estudos sobre o conhecimento ecológico local dos pescadores (FEK) vêm sendo considerados promissores para o manejo pesqueiro, porém poucos são delineados especificamente com esse fim. Este estudo objetivou investigar o conhecimento ecológico dos pescadores locais visando fornecer indicadores detalhados sobre a ocorrência espacial e sazonal dos recursos e da pesca, além de propor uma nova metodologia. Para tal, a partir de uma adaptação do método Delphi, caracterizado pela busca de consenso, foram efetuadas 3 rodadas de entrevistas a um total de 109 pescadores locais, em 12 comunidades pesqueiras e 3 pontos de desembarques. O FEK revelou-se sólido e detalhado, visto que permitiu identificar informações relevantes para o manejo pesqueiro com enfoque ecossistêmico. Foi possível encontrar consenso em questões-chave, tais como: (1) a localização dos principais \"pesqueiros\" por arte de pesca, (2) a distribuição espacial e sazonal dos principais recursos, (3) a identificação potencial de habitats essenciais e (4) sugestões para o ordenamento pesqueiro. A metodologia proposta se mostrou de grande valia para a investigação do conhecimento dos pescadores e sua aplicação prática em questões de manejo. Espera-se contribuir para planos de manejo pesqueiro que considerem a \"saúde\" do ecossistema e as necessidades dos pescadores locais. / In Ubatuba (SP), fishing shows a great socio-economic importance, and, just like elsewhere, requires an effective management. Studies on fisher\'s ecological knowledge (FEK) have been considered a promissory field for fisheries management but few efforts have been specifically delineated with such a goal. This study aimed to investigate local FEK in order to provide detailed indicators about the spatial and seasonal occurrence of fishing and its fishery resources. It also proposes a new methodology, adapted from Delphi\'s which is characterized by the search of consensus. Overall, a total of 109 local fishers were interviewed along 12 local communities and 3 landing sites in 3 sequential rounds. FEK proved to be consistent and detailed, allowing to identify important information for ecosystem-based fisheries management and find consensus on key-issues such as: (1) the locations of major fishing grounds per the different fishing gears, (2) the spatial distribution and seasonal occurrence of major fishery resources, (3) identification of potential essential fish habitats (EFH), and (4) fishers\' suggestions for local fishery management. The new methodology proved to be useful for FEK studies and its practical application for management. Thus, it is expected to contribute in local fisheries management plans that consider both the health of the ecosystem and the needs of local fishers.

Em Ubatuba (SP), a pesca apresenta grande importância sócio-econômica e requer, como em outros locais, um manejo adequado. Estudos sobre o conhecimento ecológico local dos pescadores (FEK) vêm sendo considerados promissores para o manejo pesqueiro, porém poucos são delineados especificamente com esse fim. Este estudo objetivou investigar o conhecimento ecológico dos pescadores locais visando fornecer indicadores detalhados sobre a ocorrência espacial e sazonal dos recursos e da pesca, além de propor uma nova metodologia. Para tal, a partir de uma adaptação do método Delphi, caracterizado pela busca de consenso, foram efetuadas 3 rodadas de entrevistas a um total de 109 pescadores locais, em 12 comunidades pesqueiras e 3 pontos de desembarques. O FEK revelou-se sólido e detalhado, visto que permitiu identificar informações relevantes para o manejo pesqueiro com enfoque ecossistêmico. Foi possível encontrar consenso em questões-chave, tais como: (1) a localização dos principais \"pesqueiros\" por arte de pesca, (2) a distribuição espacial e sazonal dos principais recursos, (3) a identificação potencial de habitats essenciais e (4) sugestões para o ordenamento pesqueiro. A metodologia proposta se mostrou de grande valia para a investigação do conhecimento dos pescadores e sua aplicação prática em questões de manejo. Espera-se contribuir para planos de manejo pesqueiro que considerem a \"saúde\" do ecossistema e as necessidades dos pescadores locais. / In Ubatuba (SP), fishing shows a great socio-economic importance, and, just like elsewhere, requires an effective management. Studies on fisher\'s ecological knowledge (FEK) have been considered a promissory field for fisheries management but few efforts have been specifically delineated with such a goal. This study aimed to investigate local FEK in order to provide detailed indicators about the spatial and seasonal occurrence of fishing and its fishery resources. It also proposes a new methodology, adapted from Delphi\'s which is characterized by the search of consensus. Overall, a total of 109 local fishers were interviewed along 12 local communities and 3 landing sites in 3 sequential rounds. FEK proved to be consistent and detailed, allowing to identify important information for ecosystem-based fisheries management and find consensus on key-issues such as: (1) the locations of major fishing grounds per the different fishing gears, (2) the spatial distribution and seasonal occurrence of major fishery resources, (3) identification of potential essential fish habitats (EFH), and (4) fishers\' suggestions for local fishery management. The new methodology proved to be useful for FEK studies and its practical application for management. Thus, it is expected to contribute in local fisheries management plans that consider both the health of the ecosystem and the needs of local fishers.