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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.
71

”Human uses carefully managed” : A critical discourse analysis of the Chagos Marine Protected Area

Hallgren, Axel January 2018 (has links)
The large marine protected area (MPA) declared in 2010 around the Chagos Archipelago, also known as the British Indian Ocean Territory (BIOT), has led to a conflict in the thick of environmental protection, colonialism, sovereignty claims, and the human rights dispute of the Chagossian people that once were exiled from the islands in the 1970s. By applying a Foucauldian inspired critical discourse analysis, this study interprets and examines how the nature/human relationship was portrayed during and after the creation of the Chagos MPA. Applying theories and concepts from political ecology and Foucault’s idea of biopower sheds new light on a conservation effort depicted as a global environmental success by some, and a geopolitical social justice disaster by others. Finally, this thesis applies Tim Ingold’s philosophical concept of the globe and sphere to discuss the implications of inclusion or withdrawal from nature.
72

Anthropic impacts in Mediterranean Marine Protected Areas / Impactes antròpics en àrees marines protegides mediterrànies

Luna i Pérez, Beatriz 02 June 2010 (has links)
No description available.
73

Les yeux de la mer et les médecins de la mer : des espaces sacrés des ancêtres aux aires marines protégées des vazaha sur le littoral vezo à Madagascar / Eyes from the sea and the doctors of the sea : sacred spaces of the ancestors to the marine protected areas of the vazaha on the vezo coastline in Madagascar

Veriza, Roberto Francis 17 June 2019 (has links)
La bande côtière du littoral Sud-ouest de Madagascar est occupée par le groupe des Vezo dont la pêche est le principal moyen de subsistance. Cette occupation s’inscrit dans une longue histoire depuis l’époque de la traite d’esclaves, au XVIIème siècle. Les Vezo ont fondé leur identité grâce à la pêche et à la maîtrise de la navigation, avec la mise en place de sites interdits en mer pour gérer les ressources. Au début des années 1980, les océanographes ont signalé que les écosystèmes marins et côtiers étaient « en danger ». On attribue généralement la dégradation de l’environnement à l’accroissement de la pauvreté, à une demande accrue de produits halieutiques par le marché national et international, ainsi qu’à l’augmentation du nombre des usagers de la mer. Le diagnostic négatif quant à l’évolution des écosystèmes est à l’origine de l’intervention des institutions internationales et agences de développement dès le début des années 1990. Sur le registre du développement, il s’agit alors de moderniser les pratiques traditionnelles vezo et leurs engins de pêche. Dans le même temps, les conservationnistes créent des réserves marines et assurent la promotion du « volontourisme » et de l’aquaculture. A travers l’exemple d’Andavadoake, nous analysons l’évolution de l’occupation de l’espace ainsi que celle des pratiques de pêche, dont l’originalité était la gestion des tanifaly, espaces sacrés. Quelle évolution de l’identité vezo autorise l’appréhension d’un tel changement ? Une analyse des stratégies territoriales dans leur profondeur historique nous permet de remettre en cause le classement des Vezo en groupe ethnique, ce qui est aussi une des ambitions de notre thèse. Enfin, nous évaluons dans quelle mesure la politique de mise en réserves des écosystèmes marins a participé aux transformations organisationnelles et spatiales des Vezo. / The coastal strip of the southwest of Madagascar is occupied by the group of Vezo whose fishing is the main livelihood. This occupation is part of a long history since the days of the slave trade (seventeenth century). Vezo based their identity through fishing (with the introduction of banned sites to manage marine resources) and control of navigation. In the early 1980s, oceanographers have reported that marine and coastal ecosystems are "in danger." It is generally attributed to increased poverty, a strong demand for fish products by the national and international market, and a higher number of users of the sea. The negative result in the evolution of these ecosystems is the origin of the intervention, since the early 1990s, of the international institutions and development agencies to modernize traditional vezo practices and fishing gear. Similarly, conservationists have established marine protected areas and promoted “volontourism” and aquaculture. Through the example of Andavadoake, we analyze the evolution of the use of space as well as fishing practices, whose originality was managing tanifaly "sacred sites" which changes the vezo identity. An analysis of regional strategies in their historical depth allows us to challenge the classification in Vezo ethnic group, which is also one of the goals of our thesis. Finally, we will evaluate to what extent the policy of setting reserves participated in the organizational and spatial transformations Vezo. Finally, we evaluate how expansion of marine protected areas participate in the Vezo's organizational and spatial transformations.
74

Applications of ocean transport modelling

Corell, Hanna January 2012 (has links)
The advective motion of seawater governs the transport of almost everything, animate or inanimate, present in the ocean and those lacking the ability to outswim the currents have to follow the flow. This makes modelling of advective ocean transports a powerful tool in various fields of science where a displacement of something over time is studied. The present thesis comprises four different applications of ocean-transport modelling, ranging from large-scale heat transports to the dispersion of juvenile marine organisms. The aim has been to adapt the method not only to the object of study, but also to the available model-data sets and in situ-observations. The first application in the thesis is a study of the oceanic heat transport. It illustrates the importance of wind forcing for not only the heat transport from the Indian to the Atlantic Ocean, but also for the net northward transport of heat in the Atlantic. In the next study focus is on the particle-transport differences between an open and a semi-enclosed coastal area on the Swedish coast of the Baltic Sea. The modelled patterns of sedimentation and residence times in the two basins are examined after particles having been released from a number of prescribed point sources. In the two final studies the transport-modelling framework is applied within a marine-ecology context and the transported entities are larvae of some Scandinavian sessile and sedentary species and non-commercial fishes (e.g. the bay barnacle, the blue mussel, the shore crab and the gobies). The effects of depth distribution of dispersing larvae on the efficiency of the Marine Protected Areas in the Baltic Sea are examined. Further, the diversity in dispersal and connectivity depending on vertical behaviour is modelled for regions with different tidal regimes in the North Sea, the Skagerrak and the Kattegat. The spatial scales dealt with in the studies varied from global to a highly resolved 182-metres grid. The model results, excepting those from the global study, are based on or compared with in situ-data. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted. 4: Manuscript.</p>
75

The capacity to adapt, conserve and thrive?: marine protected area communities and social-ecological change in coastal Thailand

Bennett, Nathan 08 August 2013 (has links)
Three complicated and interrelated issues are marine conservation, local development, and climate change. To seek insight into the challenges posed by these issues in a particular context, this dissertation focuses on seven communities near marine protected areas (MPAs) on the Andaman Coast of Thailand. The central question was “How can conservation outcomes and community livelihoods and adaptive capacity be enhanced in communities near MPAs on the Andaman Coast of Thailand in consideration of a changing climate?” The objectives were to explore local perceptions of social and environmental change and vulnerability, community opinions of Thailand’s National Marine Parks (NMPs), and the adaptive capacity of coastal communities. Literatures on resilience, adaptive capacity, vulnerability, conservation impacts, sustainable livelihoods, and governance and management frame the research. Fieldwork included Photovoice, interviews, and household surveys. Four stand-alone manuscripts are included in the dissertation: a) “A picture of change: Using Photovoice to explore social and environmental change in coastal communities on the Andaman Coast of Thailand”; b) “Vulnerability to multiple stressors in coastal communities: A study of the Andaman Coast of Thailand”; c) “Why local people do not support conservation: Community perceptions of marine protected area livelihood impacts, governance and management in Thailand”; and, d) “The capacity to adapt?: Communities in a changing climate, environment and economy on the northern Andaman Coast of Thailand”. Broadly, the dissertation offers relevant insights into the complex social-ecological changes being experienced by heterogeneous communities and the multi-faceted and multi-scalar actions required to address increasing challenges. Specifically, it a) demonstrates that Photovoice is an effective method for examining social and environmental change and providing input into community adaptation, conservation, and development processes, b) explores the social-economic and biophysical stressors that contribute to household vulnerability and suggests that multiple stressors, particularly economics and climate change, need to be considered in adaptation planning, c) recommends significant improvements to current NMP governance and management to engender local support for marine conservation, and d) illustrates that communities on the Andaman coast of Thailand are coping with environmental and fisheries declines, reacting to climate change and adapting variably to alternative livelihoods and proposes interventions for improving adaptive capacity. / Graduate / 0366 / njbennet@uvic.ca
76

Composição e estrutura da comunidade de peixes recifais do parque estadual marinho areia vermelha, Cabedelo, PB

Querino, Luciana Alcantara Carvalho 24 February 2011 (has links)
Made available in DSpace on 2015-04-17T14:55:28Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2453210 bytes, checksum: 30faa7ddf8d520d8e3c100c3296d8a2b (MD5) Previous issue date: 2011-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Several types of mechanisms can influence community structure of fishes in marine ecosystems, such as larval recruitment, interaction between species, abiotic factors, composition and percent cover of benthic organisms, mainly providing a relationship of habitat complexity with higher abundance and structural diversity. In this context, this study aimed to survey the reef fish fauna of coastal habitats located in the Parque Estadual Marinho Areia Vermelha, with emphasis on habitat characteristics, distribution patterns and conservation aspects recorded species in the area. The study site was divided into sampling stations according to the history of tourism activity: Areia Vermelha (AV - longer visiting history), Areia Dourada (AD - recent visiting history) and No Visit (SV - adjacent area - no visiting history). The stations were sampled by the method of stationary visual census in free-diving, with the average duration of 15 minutes and between December 2009 and April 2010, December 2010 and January 2011. Among the types of substrate coverage analyzed, there was a dominance of sessile invertebrates in AD and macroalgae in AV and SV. during the 150 censuses, a total of 6141 specimens were recorded, including by 55 species, distributed in 26 families. Labridae (Scarinae) was the family with highest abundance and Haemulidae the one with highest species richness. The species that yielded the largest number of individuals on the macroalgae environments were Sparisoma axillare, Abudefduf saxatilis, Acanthurus chirurgus, Haemulon parra and Halichoeres brasiliensis, while the reefs were Sparisoma axillare, Abudefduf saxatilis, Acanthurus chirurgus, Scarus zelindae and Halichoeres brasiliensis. Most individuals were found in the juvenile stage. With respect to trophic structure, most sighted individuals were grouped in the category Non-Territorial Herbivores. The environments analyzed in this study proved to be important for juvenile individuals of different species as well as for endangered fishes, indicating the importance of their conservation for the survival of these species. / Muitos mecanismos podem influenciar a estrutura da comunidade de peixes em ambientes marinhos, tais como o recrutamento larval, interação entre as espécies, fatores abióticos, composição e percentagem de cobertura de organismos bênticos, conferindo principalmente à complexidade do habitat uma relação com maior abundância e diversidade estrutural. Diante deste contexto, o presente trabalho objetivou inventariar a fauna de peixes recifais do Parque Estadual Marinho Areia Vermelha, com ênfase na caracterização do habitat, padrões de distribuição e aspectos da conservação das espécies registradas no Parque. A área de estudo foi dividida em estações de coleta de acordo com o histórico de turismo: Areia Vermelha (AV histórico antigo de visitação), Areia Dourada (AD histórico recente de visitação) e Sem Visita (SV área adjacente sem histórico de visitação). As estações foram amostradas pelo método do censo visual estacionário, em mergulho livre, com duração média de 15 minutos e entre dezembro de 2009 a abril de 2010, dezembro de 2010 e janeiro de 2011. Dentre os tipos de cobertura de substrato analisados, houve dominância dos invertebrados sésseis em AD e de macroalgas em AV e SV. Dos 150 censos realizados, foi registrado um total de 6.141 espécimes, representados por 55 espécies e distribuídos em 27 famílias. Labridae (Scarinae) foi o grupo com maior abundância e Haemulidae a família com maior riqueza de espécies. As espécies que perfizeram o maior número de indivíduos nos ambientes de macroalga foram Sparisoma axillare, Abudefduf saxatilis, Acanthurus chirurgus, Haemulon parra e Halichoeres brasiliensis, enquanto nos recifes foram Sparisoma axillare, A. saxatilis, A. chirurgus, Scarus zelindae e H. brasiliensis. A maioria dos indivíduos foram encontrados no estágio juvenil. Em relação às categorias tróficas, a maior parte dos indivíduos avistados foi agrupada na categoria Herbívoros não territorialistas. Os ambientes analisados no presente estudo mostraram ser importantes para indivíduos jovens de variadas espécies, bem como para peixes considerados ameaçados de extinção, o que remete a importância da conservação de tais ambientes para a sobrevivência destas espécies.
77

Dinâmica temporal e influência de variáveis ambientais no recrutamento de peixes recifais do Banco dos Abrolho, BA, Brasil. / Temporal dynamics and influence of environmental variables in the recruitment of reef fish of the Abrolhos Bank, Brazil

Daniel Sartor 25 June 2015 (has links)
O recrutamento é extremamente importante no ambiente recifal, sendo o principal responsável pelo reabastecimento de populações adultas de peixes. Esse fenômeno é altamente complexo, não sendo claro se é influenciado apenas por processos estocásticos ou também por processos determinísticos. No presente estudo avaliamos a dinâmica temporal do recrutamento de diversas espécies de peixes recifais, identificando sítios de berçário (i.e. recrutamento estável e alto) e a influência de variáveis ambientais. Para tal, utilizamos dados de um monitoramento de médio prazo (i.e. 2001 a 2014) realizado no Banco dos Abrolhos (BA-Brasil). Foram amostrados mais de 45 sítios, sendo levantados dados sobre a comunidade de peixes, comunidade bentônica e outras variáveis ambientais. A partir desses dados, avaliamos a variação do recrutamento por sítio em dois períodos distintos (i.e. 2001-2008/2006-2014) e a influência de variáveis ambientais no recrutamento, através da técnica Boosted Regression Trees. Constatamos que diversas espécies de peixe apresentam-se com recrutamento estável em distintos sítios de amostragem. Também observamos um efeito positivo da densidade de peixes recifais coespecíficos adultos e da cobertura relativa de algas frondosas no recrutamento de diversas espécies analisadas. No geral, observamos que há certa espécie especificidade no processo de recrutamento, porém, em escalas espaciais maiores, os padrões podem estar ligados a características mais gerais, relacionadas a um grupo taxonômico mais elevado. Em relação aos sítios de berçário, um se destacou, sendo berçário de 5 diferentes espécies, incluindo Scarus trispinosus, uma das espécies prioritárias para conservação na região de Abrolhos. Assim, recomendamos a criação de uma área marinha de proteção integral que englobe o sítio em questão. Além disso, as descobertas deste trabalho nos permitem reforçar a teoria de que o recrutamento de peixes recifais pode ser influenciado por fenômenos determinísticos e não varia simplesmente de maneira estocástica. / Recruitment is extremely important in the reef environment, because it is the main source of population replenishment. Reef fish recruitment is a highly complex process and it is not clear whether it is influenced only by stochastic processes or also by deterministic processes. Herein, we aimed to investigate temporal dynamics of reef fish recruitment, identify nursery sites (i.e. predictably high recruitment sites) and evaluate the influence of environmental variables on recruitment. We used data from a medium-term time series (i.e. 2001-2014) of scientific surveys in Abrolhos Bank (BA-Brazil). We sampled more than 45 sites, for several consecutive years and recorded data about fish community, benthic community and other environmental variables. We assessed the variation of recruitment on each site, during two distinct periods (i.e. 2001-2008 / 2006-2014), and used the Boosted Regression Trees technique to evaluate the influence of environmental variables in recruitment. We found that several reef fish species present a low variable recruitment at different sampling sites. BRT showed a positive effect of the coverage of flesh algae and abundance of conspecific in the abundance of recruits (i.e. young-of-year) of many species. Overall, we notice that the recruitment traits seems to be species specific, but we also found indications that in larger spatial scales, recruitment spatial and temporal patterns may be related to general characteristics among species of the higher taxa. Nursery sites varied among species and one site was a nursery to 5 different reef fish species, including Scarus trispinosus, a species that require priority conservation in the Abrolhos Bank. Therefore, we recommend the creation of a new no-take marine protected area that encompasses this site. Our results also indicated that reef fish recruitment may be influenced by deterministic processes and do not vary only stochastically.
78

Benthic Invertebrate Communities and Habitat Characterization of the Pourtalès Terrace, Florida with Analysis of the Deepwater Coral Habitat Areas of Particular Concern and the East Hump Marine Protected Area

Ash, Jana K. 31 July 2015 (has links)
The Pourtalès Terrace is a gently curved, narrow triangular platform that parallels the Florida Keys for 213 km running from southern Key Largo to between Key West and the Marquesas Keys. The main Terrace surface begins in 200 m and dips gently to approximately 450 m, where the Pourtalès Escarpment slopes steeply to the deep floor of the southern Straits of Florida. The Terrace platform exhibits a wide variety of Neogene-age geological features, including high-relief ledges, mounds, sinkholes and deep-water biogenic build-ups called bioherms. Previous research revealed dense and diverse benthic assemblages dominated by stylasterid hydrocorals, octocorals and sponges. Many Terrace features also represent popular, long-term fishing targets. Due to concerns about resource sustainability, (National Oceanic and Atmospheric Administration (NOAA) and the South Atlantic Fishery Management Council (SAFMC) included the Terrace in the Comprehensive Ecosystem-Based Amendment 1 (CE-BA 1, June 2010) that protects deep-water Coral Habitat Areas of Particular Concern (CHAPCs) along the southeastern U.S continental margin by prohibiting use of a variety of potentially damaging bottom fishing gear. NOAA also established the East Hump Marine Protected Area (MPA) as a Type II MPA, permanently closed to fishing for and possession of snapper and grouper species. To develop a more robust database on Terrace habitats and resources, a research cruise (September 2011) used ROV Kraken 2 to survey 14 sites both inside and outside the CHAPC and MPA for biological diversity, density, and distribution, with a focus on deep-sea coral and sponge assemblages. The surveys resulted in 58 h of videotape, 2,866 images, and collected 150 specimens of benthic invertebrates. All dive sites were mapped with multibeam sonar. This project used Coral Point Count with Excel extensions (CPCe)©, PRIMER 6.1.10 beta, JMP© statistical software, and Environmental Systems Research Institute (ESRI) ArcMap 10.3 Geographic Information Systems (GIS) to quantitatively analyze transect images and video from the ROV transects. This information was used to characterize dive sites in terms of benthic invertebrate faunal communities, depth, and topography; and compare results relative to protected versus unprotected sites. Of the 14 sites surveyed 10 were analyzed and split into 42 transects of approximately 30 m2 based on five depth and location bin classes. Each site was initially separated into habitat types based on qualitative geomorphologic features for statistical analysis (i.e., mound slope, mound wall, mound top, deep mound, valley, Lophelia mound, sinkhole), using methods established by Reed et al. (2011; 2014). In initial analysis, depth and location were found to be superior to geomorphology as an indicator of what was driving differences in communities among transects. As a result each transect was placed into one of five depth and location bin classes based on depth (m) of each image and location relating to CHAPC/MPA area borders: West 150-300 m (12 transects), North Central 150-250 m (14), Central 250-300 m (8), South 450-500m (5) and South 500-550 m (3). Distinct differences in communities of each depth and location bin class in relation to percent cover and organism density were apparent. Communities vary strongly among bins with some similarities: e.g., West 150-300, North-Central 150-250, and Central 250-300 all included Stylaster miniatus (Stylasteridae): South 450-500 and South 500-550 included Paramuricea sp. 3 among their most dominant species. Also similar species were found within similar depth ranges. Protection status (within CHAPC, CHAPC/MPA, or No Protection) did not affect differences in communities, suggesting protection regulations have not been implemented long enough to show significant differences between protected and unprotected sites. Several new geologic features were found e.g., the southernmost Lophelia pertusa coral mound in U.S. waters. Some important features were described that lie outside of CHAPC/MPA borders, suggesting new borders should be designated. Results showed a strong relationship between depth and location in forming deep-water communities, and that these factors could be used as proxies for creating habitat maps in unmapped areas. These results will also provide managers and scientists with a valuable baseline for assessing benthic invertebrate communities, their changes over time, and the effectiveness of protected areas on the Pourtalès Terrace.
79

Marina ekosystemtjänster för Hav i balans samt levande kust och skärgård : En kvalitativ analys av lokal förvaltning av Höga Kusten och Sankt Anna-Missjö / Marine ecosystem services for A Balanced Marine Environment, Flourishing Coastal Areas and Archipelagos : A qualitative analysis of local management in the High Coast and St. Anna-Missjö

Augustinsson Malmberg, Elliot, Lagerhjelm, Charlotte January 2021 (has links)
Östersjön omfattas av en stor mångfald marina ekosystemtjänster som livnär närliggande samhällen. Deras funktion är hotad av en mängd terrestra och akvatiska aktiviteter som har förorenat havet, vilket kräver en långsiktig hållbar förvaltning. Syftet med denna uppsats är att bidra med kunskap om och förstå utmaningar och möjligheter i att uppnå en god ekologisk status i Östersjön. Studien baseras på en granskning av förvaltningsmetoder hos länsstyrelser och kommuner i två områden som är skyddade av den regionala överenskommelsen Helsingforskonventionen; Höga Kusten i Västernorrland och S:t Anna-Missjö i Östergötland. Till grund för det analytiska ramverket ligger Havs- och vattenmyndighetens rapport, som beskriver ekosystemtjänster som Östersjön bidrar med, samt även tjänsternas status, åtgärder och utmaningar som uppstår vid förvaltning. Resultatet baseras på kvalitativa metoder för att samla in data, genom att specifikt studera dokument samt intervjuer med lokala tjänstemän. Den insamlade empirin har blivit kategoriserad och analyserad i linje med Havs- och vattenmyndighetens rapport, därefter har innehållet diskuterats. Resultatet visar att mest fokus lades på hantering av övergödning, ohållbart fiske och reglering av föroreningar, samt deras trade-off- och synergieffekter som påverkar förvaltningen av just dessa ekosystemtjänster. Följaktligen, är det nödvändigt för tjänstemän att samverka med lokalbefolkningen för att uppnå en hållbar förvaltning av de skyddade områdena och deras ekosystemtjänster. Generella utmaningar ansågs vara tid, resurser och kunskap för förvaltning av marina miljöer. Dock genomsyrar myndighetens ramverk om ekosystemtjänster stora delar av länsstyrelserna och kommunernas arbete med marin förvaltning på Höga Kusten och S:t Anna-Missjö. Ekosystemtjänsternas status och funktioner är integrerade i länens och kommunernas förvaltningsmetoder av de skyddade områdena. Ekosystemtjänster som begrepp är däremot frånvarande och inte explicit nämnt i arbetet. / The Baltic Sea offers a diversity of marine ecosystem services which is providing support to nearby human communities. Their functions are jeopardized by terrestrial and aquatic activities which have heavily polluted the sea, necessitating long-term sustainable management. The aim of this bachelor thesis is to provide a scientific contribution to understanding the challenges and opportunities for reaching a good ecological status in the Baltic Sea, as well as insight into the ongoing management practices of Swedish county administrative boards and municipalities. Practices that involve conserving ecosystem services in two different marine protected areas the High Coast and St. Anna-Missjö, both of which have been designated important by a regional convention; the Helsinki Commission. Therefore, the Swedish Agency for Marine and Water Management has adopted a report on which ecosystem services the Baltic Sea provides, and the status of the services in different parts of the sea. This study is based on qualitative methods to gather data by a thorough reading of documents written by the counties and semi-structured interviews of local officials. The data has summarily been categorised and analysed in line with the national agency’s report, then discussed afterwards. The results show that the management practices were heavily emphasised on dealing with activities that lead to eutrophication, unsustainable fishery as well as regulation of polluting substances; where trade-offs and synergy-effects converge that impacts the management of other marine ecosystem services. Hence, it is necessary for officials to network with locals to have sustainable management of the protected areas and their ecosystem services. The officials pointed to the presence of a lack of time, resources and expertise in managing marine environments. Although the agency’s perspective on marine ecosystem services permeates large parts of county administrative boards and municipalities' work with marine management in the High Coast and St. Anna-Missjö. The status and functions of ecosystem services are integrated in their management practices of the protected areas. However, the concepts themselves are more absent and not mentioned explicitly.
80

The Ecological and Anthropogenic Impacts of fishing gear in a tropical system : How the size of Spotted Rose Snapper (Lutjanus guttatus) and the ratio of target catch, is influenced by approved fishing gear within a marine area of responsible fishing in the South-Western Gulf of Nicoya, Costa Rica.

Eriksson, Alfred January 2023 (has links)
The oceans are essential for humanity, yet these systems continue to be degraded and suffer from pollution, habitat destruction and overexploitation. The Costa Rican Gulf of Nicoya is a productive gulf that is fished by both large-scale industrial fisheries and small-scale artisanal fishermen. However, the gulf is profoundly overfished and there has been a shift in both the type of species and size of fishes being targeted, which has had devastating economic and ecological effects in the region. To improve their livelihoods, artisanal fishermen have together with governmental agencies instituted partially protected marine protected areas, known as AMPRs which are intended to give artisanal fishermen exclusive fishing rights and to better the health of the ecosystems. However, these AMPRs can vary greatly within and between each other in aspects such as what types of fishing gear is allowed. To investigate how fishing techniques impact the health of the fish stocks and the wellbeing of fishermen within an AMPR, the size of a target fish, Spotted Rose Snapper (Lutjanus guttatus) and the number of undesired fish caught, was compared based on the number of approved fishing methods such as nets, longlines and commercial scuba diving, between different zones. This was conducted by identifying and measuring catch in collaboration with the National University of Costa Rica, who contributed with databases and field assistance, and artisanal dead bait longline fishermen (bottom long line) in the Paquera-Tambor AMPR. The results showed that in areas where fishing gear is more restricted, the mean weight of Spotted Rose Snapper was higher, but the relative proportion bycatch was not different. Furthermore, there was no difference in legal capture or breeding lengths between areas with high and low restriction of fishing gear. This indicates that the effects of overfishing are less predominant in zones where fewer fishing methods are permitted. The restriction of fishing methods could increase biodiversity and size in fish by exploiting less cohorts of populations. The preservation of size in fish species is very important regarding reproductive success, and it is therefore paramount that larger individuals are protected. This could be accomplished by for example, restricting the amount of allowed fishing gear or introducing maximum catch sizes. However, an improvement of the fish stocks, and therefore human wellbeing cannot be achieved in the Gulf of Nicoya without a revision of the strategies of two influential governmental bodies, the Costa Rican coast guard and the Costa Rican Institute of Fisheries and Aquaculture.

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