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The spatial characterization of Puerto Rican commercial fisheries describing fishing gear use in relation to habitat classes and bathymetry ranges was achieved through the collection and analysis of spatial fisheries data. An extensive field data gathering session was conducted in the entire Puerto Rican territory during the summer months of 2009, from June to October. The field data was digitized and analyzed using geographic information systems (GIS) and computer spreadsheet software, and gear usage charts and graphs, fishing grounds maps, and fishing intensity maps were produced for four gear categories: line, net, dive, and trap gears. Patterns and evidence of likely relationships linking gear usage and benthic habitat, and between gear utilization and water depth ranges, were presented. The importance of the spatial characterization of the commercial fishery for Puerto Rican fisheries management, and other recommendations were given within the concluding chapter.

Made available in DSpace on 2015-04-11T13:56:34Z (GMT). No. of bitstreams: 1 Capa1.pdf: 76596 bytes, checksum: 741af4415497f149787c8fbd9442667d (MD5) Previous issue date: 2009-02-18 / In the present study, the commercial fishing potential of the municipality of Coari, Amazonas, Brazil, was evaluated based on the characterization of the regional fleet and also by the fishing landing from the period of December 1st, 2007 to November 30th, 2008. The characterization of the fleet was based on the interview of 217 fishermen e vessel owners. They identified 41 boats and 176 motorized canoes. Among these, a pattern was found in their length (canoes ≤ 10m; boats ≤ 17m), fishing storage capacity (canoes ≤ 2t, boats ≤ 10t) and displacement capacity based on their engine propulsion power (canoe > 5,5HP; boat > 30HP). This information brought together estimates the region s fishing potential and its efficiency when this is crossed with the fishing landing in kilos. Other factors that contribute to the characterization of the activity are the exploited environment, the major tools used in fisheries and the target species. It was registered 311 landings near the municipal market (community commercial place) during the year. A total of 1.014.078 kg of fish was catched with a month average of 84,506 kg (+23,944), in which the maximum amount was 129,681 kg in May 2008 and a minimum of 55,884 kg in January 2008. An amount of 35 species or groups of species was registered. The major component species of the total catch were jaraqui (Semaprochilodus spp.) (26,90%), curimatã (Prochilodus nigricans) (14,07%), tambaqui (Colossoma macropomum) (9,70%) and aruanã (Osteoglossum bicirrhosum) (6,71%). This group was responsible for 57,38% of the total fish catched in the studied period. / Neste estudo, foi avaliado o potencial da pesca comercial no município de Coari, Amazonas, Brasil, por meio da caracterização da frota que atua na região e do desembarque pesqueiro realizado no período de 1 de Dezembro de 2007 a 30 de Novembro de 2008. A frota foi caracterizada com base nas entrevistas de 217 pescadores e donos de embarcação, os quais identificaram a atuação de 41 barcos e 176 canoas motorizadas. Estas embarcações apresentaram um padrão com relação ao comprimento (canoas ≤ 10m; barcos ≤ 17m), capacidade de armazenamento de pescado (canoas ≤ 2t; barcos ≤ 10t) e capacidade de deslocamento com potência média de motores de propulsão de 5,5hp para as canoas e de 30hp para os barcos. Estas informações associadas estimam o potencial pesqueiro da região e sua eficiência quando relacionadas ao resultado do desembarque pesqueiro em quilos. Outros fatores como o ambiente explotado, principais apetrechos e espécies-alvo complementam a caracterização da atividade. Foram registrados, ao longo do ano, em média, 311 desembarques no porto próximo ao mercado municipal, local de comercialização do pescado ao consumidor. A produção total de pescado foi de 1.014.078 kg, com média mensal de 84.506 kg (±23.944kg), sendo a máxima de 129.681 kg ocorrida no mês de maio de 2008 e a mínima de 55.884 kg ocorrida no mês de janeiro de 2008. Foram registradas 35 espécies ou grupos de espécies de peixes responsáveis pela composição do desembarque. A produção de pescado em quilos teve como principais representantes o jaraqui (Semaprochilodus spp.) (26,90%), o curimatã (Prochilodus nigricans) (14,07%), o tambaqui (Colossoma macropomum) (9,70%) e a aruanã (Osteoglossum bicirrhosum) (6,71%), sendo este grupo responsável por 57,38% do desembarque total efetuado no período estudado.

Reef fisheries are important activities that support the livelihoods of millions of people. Reef fisheries exploit different habitats and typically target a diversity of species caught with a matching diversity of fishing gears. However, previous studies of reef fisheries have generally lacked detailed information on the catch and effort by gear and habitat type. In this dissertation, the sustainability of a coral reef fishery at the Marine Protected Area Costa dos Corais, Northeastern Brazil is assessed. In 1,833 landing interviews with local fishers, 100 fished species were identified and the total catch in kilograms for each species, the size composition of captured individuals and the habitat type exploited were recorded. First, the dissertation explores how fishing gears selected for distinct functional traits. A low competitive interaction between different gears was noted. Gears used in reef habitats selected for sedentary and benthic species, while gears used in coastal lagoons targeted highly mobile and pelagic. Second, the dissertation assesses how different gear affected the catch rates of coral reef fishes. Gears used on coral reef habitats had a more negative effect on catch rates than those used in coastal lagoons. The three gear types that affected catch rates more severely were hook and line, gillnet and cast net. Based on the results it is argued that the effects of reef fisheries on catch rates were highly depended on the vulnerability of target species. Finally, the dissertation assesses the ability of the fishing-down concept to assess the sustainability of the local fishery; the fishing-down is used to describe the process of moving away from catching large fish to progressively targeting smaller fish. I found strong support for the fishing-down, as fisheries decreased the average size of the fish assemblage and affected more heavily the catch rates of fishes with higher index of vulnerability. Overall results show that fisheries management should focus on the conservation of vulnerable taxa that are responsible for key ecological processes in coral reefs such as herbivory and coral predation. The decision-making process on management measures must be based on clear discussions with all stakeholders involved. / Doctor of Philosophy / Coral reefs are one of the richest environments on the planet, but overfishing threatens their conservation. Reef fishers use many techniques, or fishing gears, such as hook and line and nets, to catch a high diversity of fish species. Reef fisheries are often unsustainable as fishers are allowed to employ high levels of effort. Thus, studies are needed to assess the sustainability of coral reef fisheries and determine which gears are more negative to reef fishes. In a series of three studies, I investigated how reef fisheries affected fish communities in Northeastern Brazil. I used a total of 1,833 interviews with fishers in which I recorded the total catch for each species, obtained size of fish individuals, and asked about the environment that was exploited, coral reefs or coastal lagoons. First, I evaluated how the different gears selected for groups of species with unique life-history characteristics, such as size, mobility and period of activity. I found that gears such as hook and line and harpoon selected for species with sedentary traits that live near the bottom of the ocean, whereas nets selected for very mobile species that inhabit surface waters. In general, fishers did not compete for the same resources with different gears. Second, I assessed how the different gears affected the relative abundance of coral reef fishes. The three gear types that affected more heavily the relative abundance of fishes were hook and line, gillnet and cast net. I argue that the negative effects occurred because these gears caught species with characteristics that made them vulnerable to exploitation, such as slow body growth. Third the dissertation assesses the ability of the fishing-down concept to assess the sustainability of the local fishery; the fishing-down is used to describe the process of moving away from catching large fish to progressively targeting smaller fish. I found strong support for the fishing-down as the studied fisheries impacted the size and the abundance of local fishes. My results suggest that fisheries management should focus on the conservation of vulnerable fish responsible for key ecological processes such as herbivory and coral predation. The decision-making process regarding fisheries management must also be based on clear discussions with all stakeholders involved.

Masters Research - Master of Science / This thesis investigates the livelihoods of fishermen in the villages in Cijulang, West Java, Indonesia. The research used community based coastal resource management and participatory coastal resource assessment to provide an indepth look at three small fishing communities. It addresses the perceived low income and standard of living of small-scale fishers in Indonesia and, by doing so, informs on the validity of these problems, factors that may be causing these problems, and possible fisheries management interventions that may be considered to improve the situation of fishers in one area of Indonesia. The thesis presents the results of research conducted in the three fishing villages in 2004 and 2005, the economic and social impact of an 85% fuel price rise and its relationship to fishing gear ownership and use. The thesis looks at the assumption that fishermen are the ‘poorest of the poor’, discusses the large disparity between the incomes of fishers from both an inter- and intra- village perspective, and highlights that ownership and use of different types of fishing gears has a strong impact on the earning power of small-scale fishermen. The thesis also investigates the impact of the environment on fishing frequency and challenges the assumption that research conducted in one part of Indonesia is valid for other areas. It does this through describing the concepts of an ‘angry ocean’ and ‘calm sea’, how these impact on fishing frequency, and the need to take meteorological and oceanic conditions into consideration when assessing managerial interventions and programs for small-scale fisheries in Indonesia.

La pêche repose sur des formes variées d’appropriation sociale des milieux aquatiques. Cette thèse s’attache à les définir dans le contexte particulier du bas Oyapock, estuaire d’un fleuve amazonien marquant la frontière entre la Guyane (France) et l’état d’Amapá (Brésil). Cet estuaire présente une importante diversité d’écosystèmes aquatiques (rivières, fleuves, forêts inondées, marais, mangrove et mer) et d’espèces végétales et animales qui les composent (près de 200 espèces y sont pêchées). La population du bas Oyapock forme un creuset culturel réunissant principalement Amérindiens, Créoles et Brésiliens, implantés dans deux villes et 40 villages. Par ailleurs, la présence d’un parc national sur le littoral brésilien et de trois territoires amérindiens implique des réglementations de l’accès aux ressources diverses. Dans ce contexte riche en diversité écologique et culturelle où émergent des conflits d’usage sur les territoires de pêche, cette thèse propose une lecture des dynamiques d’appropriation des ressources aquatiques. Les résultats s’appuient sur des données ethnographiques collectées d’octobre 2012 à octobre 2014. Celles-ci comprennent plus de 70 entretiens, 32 observations de sorties de pêche, l’inventaire du matériel de pêche, l’identification de 195 espèces pêchées et l’étude des taxonomies locales. L’étude des savoirs des pêcheurs révèle une connaissance fine des milieux aquatiques et de leurs rythmes, de l’écologie et de l’éthologie des animaux. Les pêcheurs fabriquent une grande variété d’engins de pêche adaptés tant aux espèces qu’aux espaces. Sur la base des savoirs partagés par les pêcheurs, différents groupes se distinguent et se spécialisent en fonction de grands milieux écologiques (savanes; fleuve et forêt ; embouchure et mer). La création de parcs nationaux, le contrôle croissant des flux transfrontaliers, l’urbanisation et la migration sont autant de changements contemporains auxquels les pêcheurs doivent faire face. Dans ce contexte, trois groupes d’habitants se démarquent : les pêcheurs professionnels de Saint-Georges (Guyane), ceux d’Oiapoque (Brésil) et les villageois Amérindiens de l’Uaçá (Brésil). Ils s’inscrivent dans une démarche de reconnaissance formelle de leur territoires de pêche afin d’en garantir l’accès à long terme. Engagés dans différentes stratégies, la réussite de leur démarche dépend de la prise en compte de leurs spécificités par les États. / Fishing is based on various forms of social appropriation of aquatic environment. This thesis seeks to define them in the specific context of the Lower Oyapock, estuary of an Amazonian river delineating the border between French Guyana and Amapá state (Brazil). This estuary presents a high variety of aquatic ecosystems (streams, rivers, flooded forests, swamps, mangroves and sea) and is home of high diversity of plant and animal species (over 200 species are caught). The population of the Lower Oyapock forms a cultural melting-pot principally composed by Amerindians, Creoles and Brazilians, established in two towns and 40 villages. Moreover, the presence of a national park along the Brazilian coast and three indigenous lands imply a regulation of access to natural resources. In this context rich in ecological and cultural diversity, where emerge conflicts over fishing territories, this thesis proposes a reading of the dynamics of appropriation of aquatic resources. Results are based on ethnographic data collected from October 2012 to October 2014. They range from more than 70 interviews, 32 fishing trips observations, the inventory of fishing gear, the identification of 195 fishes species, and a study of local taxonomies. The study of fishers’ knowledge reveals a detailed expertise about the aquatic environments, notably their rhythms, and the animal ecology and behavior. Fishermen make an important variety of fishing equipment adapted to both species and spaces. Based on the way knowledge is shared, different fishermen’s groups are characterized and specialized according to the ecological conditions/features (savanna; river and forests; river mouth and sea). Creation of national parks, increasing controls of cross-border flows, urbanization and migration are all contemporary challenges the fishermen are confronting. In this context, three residents groups stand out: professional fishermen from Saint-Georges (French Guyana), those from Oiapoque (Brazil), and the Indigenous villagers from Uaçá (Brazil). These three groups aim to obtain an official recognition of their fishing territories in order to ensure long-term access. Engaged in various strategies, their success in the process hinges on the States’ consideration of their specificities.

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.

Textilindustrin är i behov av nya material som kräver mindre resurser än konventionellt använda material som exempelvis syntet- och bomull. Syntetiska material har en negativ påverkan på miljön, bland annat på grund av den mängd mikroplaster som släpps ut i naturen vid produktion och användning (Nagamine, Kobayashi, Kusumi & Wada 2022). En industri där syntetiska material ligger till grund för stora problem för marint liv är fiskeindustrin. När syntetiska nät tappas, oftast tillverkade av polyamid, fortsätter de att fånga fisk som inte tas om hand. Detta fenomen kallas spökfiske och skulle kunna motverkas om de syntetiska näten ersattes med ett naturligt biologiskt nedbrytbart material. Pappersgarn är ett relativt nytt material inom textilindustrin och har många egenskaper som är önskvärda vid användning i ett fiskenät, speciellt det faktum att det är biologiskt nedbrytbart. Denna studie undersöker möjligheten att använda ett pappersgarn i fiskeutrustning, närmare bestämt en kräftmjärde. Studien undersöker tre olika pappersgarn med olika grovlek, det vill säga Tex (92, 218 och 1814). Experiment utförs på garnets draghållfasthet och nedbrytningsförmåga. Ett test i bristningsstyrka görs på nät tillverkade av garnen. Testerna visar att garn med Tex 1814 är det mest lämpliga att använda i en kräftmjärde. Detta garn hade en draghållfasthet, efter 14 dagar i naturligt havsvatten, på 10541 centinewton/tex [cN/tex]. Nätet tillverkat av samma garn hade en genomsnittlig bristningsstyrka på 136 kilopascal [kPa], vilket var över den genomsnittliga bristningsstyrkan för ett nät i polyamid. Om syntetisk fiskeutrustning skulle ersättas med biologiskt nedbrytbart pappersgarn skulle det kunna motverka spökfiske och minska mängden mikroplaster i naturen. / The textile industry is in need of new materials that use less resources than conventionally used material such as synthetics and cotton. Furthermore, synthetic materials have a negative impact on the environment partly due to the amount of micro plastics that are released in nature during production and use (Nagamine, Kobayashi, Kusumi & Wada 2022). One area where synthetic materials are causing a lot of damage is the fishing industry. Synthetic nets that are lost or dropped keep catching fish that are not taken care of. This phenomenon is called ghost fishing and could be solved if the synthetics were replaced with a natural biodegradable material. Paper yarn is a relatively new material in the textile industry and has many properties that are preferred if used in a fishing net, especially the fact that it is biodegradable. This study investigates the possibility of using a paper yarn in fishing gear, more specifically a crayfish trap. The study examines three different paper yarns with different weight, also called Tex (92, 218 and 1814). Experiments are done on the yarn's tensile strength and degradability. A bursting strength test is made on nets made out of the yarns. The tests show that yarn with Tex 1814 is the most suitable to use in a crayfish trap. This yarn had a tensile strength, after 14 days in natural seawater, of 10541 centinewton/tex [cN/tex]. The net made of the same yarn had an average bursting strength of 136 kilopascal [kPa] which was above the average bursting strength of a polyamide net. If synthetic fishing gear would be replaced with biodegradable paper yarn, this could counteract ghost fishing and reduce micro plastics ending up in nature.