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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.
241

Fishermen, Politics, and Participation: An Ethnographic Examination of Commercial Fisheries Management in St. Croix, U.S. Virgin Islands

Grace-Mccaskey, Cynthia 01 January 2012 (has links)
Currently, there is widespread debate regarding the overall status of the world's fisheries, with some researchers projecting their total collapse in only a few decades, and others concluding the situation is not quite as bleak. Additional debates include what strategies should be used to manage fisheries at various scales, and further research is needed to determine which strategies are most appropriate for use in particular situations and locales, as context is critical. Recently, prominent common pool resources scholars have expressed the need for ethnographic approaches to studying resource management institutions in order to move beyond the current focus of simply identifying the factors and conditions that lead to the self-organization of resource users and long-term sustainability of management institutions. These authors describe the need for examining the larger context in which management institutions exist and taking various historical, political, and sociocultural factors into account when examining common pool resources. This dissertation is a response to that request. This research is the result of over 20 months of ethnographic research in St. Croix, United States Virgin Islands (USVI). Drawing on research in political ecology and building on anthropological critiques of common pool resource institutions, I describe the historical, social, and political factors that influence how fisheries management occurs at the federal and territorial levels, and how commercial fishers, managers, and other stakeholders experience and participate in multi-scale management processes. Ethnographic data suggest that there are a variety of historical, social, and political factors that influence how commercial fishers, managers, and other stakeholders perceive the federal fisheries management process, the extent of their participation in that process, as well as interactions within and between stakeholder groups. Additionally, the mismatch that exists between the centralized management structure of the US federal system and the small-scale, multi-method nature of St. Croix's fishery creates a complex management environment in which few stakeholders participate.
242

Restoration of Mauri (Life-Force) to Okahu Bay: Investigation of the Cultural, Social, and Environmental Restoration

Freilich, Emily 01 January 2018 (has links)
This thesis investigated the restoration of mauri (life-force) to Ōkahu Bay, Auckland New Zealand. Ōkahu Bay is part of the land and waters of Ngāti Whātua Ōrākei, a Māori hapū (sub-tribe). Ngāti Whātua Ōrākei has been driving the restoration, restoring Ōkahu Bay based on their worldview, visions, and concerns. This vision and control of the restoration process allows them to bring in the hapū in sustainable engagement and have the long-term vision and commitment necessary for self-determination. However, while there has been progress with projects and improved decision-making authority, hapū members are still not seeing their whānau (family) swimming in and caring for Ōkahu as much as they would like. Interviewees wanted to see an explicit focus on encouraging hapū members to use the bay, such as more educational programs and water-based activities, and continued efforts to improve water quality. Shellfish populations have also not recovered after a decade of monitoring due to structural aspects such as existing stormwater pipes. Changing these requires Auckland City Council to make stronger commitments to supporting Ngāti Whātua’s restoration. Overall, this investigation showed that in this restoration, a clean environment is essential to build community and a community is essential to build a clean environment. This community-driven restoration, while not perfect, has great potential to truly reconnect people with their environments, decolonize the land and the people, and create thriving ecosystems and people that benefit themselves, their communities, and the wider Auckland community.
243

Rede ?gua: instrumento de constru??o colaborativa e democratiza??o do conhecimento, direcionado as cadeias produtivas da pesca e da aq?icultura Proposta de metodologia

Morais, Ricardo S?vio Trigueiro de 16 November 2009 (has links)
Made available in DSpace on 2014-12-17T14:52:48Z (GMT). No. of bitstreams: 1 RicardoSTM_DISSERT.pdf: 1871227 bytes, checksum: ecd89b91f1ede04d56a5d1da6dbee8e5 (MD5) Previous issue date: 2009-11-16 / Universidade Federal do Rio Grande do Norte / This paper proposes a methodology for building Information Technology solutions in the form of virtual environments that allow for collaborative construction and democratization of knowledge for and about supply chains, providing tools for collaboration iteration and the social actors involved, valuing its environmental variables and assisting in its development. The scope of supply chains of aquaculture and fisheries and www.redeagua.com.br were the objects of research and prototyping of this paper. AVA Moodle was chosen to create the environment in question by their full fitness the socio-cultural characteristics of the target audience and the structure of existing digital inclusion, making necessary the development of strategies to generate interest from productive agents in their effective participation as collaborators and not just as recipients of content. The structure of this survey work will be qualitative-quantitative, using both traditional elements such as forms and interviews as sources typical of virtual environments, such as statistical reports of visitation and placement in search engines on the Internet / Este trabalho apresenta uma proposta de metodologia para constru??o de solu??es computacionais na forma de ambientes virtuais que permitam a constru??o colaborativa e a democratiza??o do conhecimento para e sobre as cadeias produtivas, disponibilizando instrumentos de itera??o e colabora??o aos atores sociais envolvidos, valorizando transversalmente suas vari?veis socioambientais e auxiliando em seu desenvolvimento sustent?vel. O escopo das cadeias produtivas da aquicultura e da pesca e o www.redeagua.com.br foram os objetos de pesquisa e prototipa??o deste trabalho. O AVA Moodle foi o escolhido para criar o ambiente em quest?o por sua plena adequabilidade as caracter?sticas s?cio-culturais do p?blico alvo e da estrutura de inclus?o digital j? existente, fazendo-se necess?ria a elabora??o de estrat?gias para gera??o de interesse por parte dos agentes produtivos na efetiva participa??o destes como colaboradores e n?o apenas como receptores de conte?dos. A estrutura da pesquisa realizada neste trabalho ser? qualiquantitativa, utilizando tanto elementos tradicionais como formul?rios e entrevistas, como fontes t?picas de ambientes virtuais, como relat?rios estat?sticos de visita??o e posicionamento nos mecanismos de busca na internet
244

Investigating the Driving Mechanisms Behind Differences in Bleaching and Disease Susceptibility Between Two Scleractinian Corals, Pseudodiploria Strigosa and Diploria Labyrinthiformis

Pratte, Zoe A 15 June 2015 (has links)
Disease and bleaching are two conditions which commonly lead to coral death. Among coral species, susceptibility to disease and bleaching is variable, and Pseudodiploria strigosa tends to be diseased more than Diploria labyrinthiformis, while D. labyrinthiformis bleaches more readily. The focus of this dissertation was to investigate and compare multiple components of these two coral species, and identify how they may relate to disease and bleaching resistance. Compenetnts examined included the surface mucopolysacharide layer (SML) thickness, gene expression, microbial associates, and a white plague aquarium study. The SML thickness decresased with increasing temperature regardless of coral species, indicating that SML thickness does not likely play a role in differences between susceptablities of these two coral species. However, Diploria labyrinthiformis had a lower mortality rate at 31°C, had fewer differentially expressed genes assossiated with stress, and upregulated genes associated with innate immunity in the summer, all of which may contribute to its relative disease resistance. The bacterial associates of each coral species were also monitored. Differences between the two coral species were primarily caused by Clostridia, Gammaproteobacteria, and rare species which may contribute to the relatively higher disease susceptibility of P. strigosa. Lastly, an aquarium study suggested that a potential pathogen of the Roseobacter clade infects both D. labyrinthiformis and P. strigosa, and might be transmitted by the Cryptochiridae gall crab, indicating that potential disease vectors associated with these two coral species may also play a role in disease resistance and resilience.
245

Non-Lethal Methods for Assessing Reproductive Status in Bonnethead Sharks (Sphyrna tiburo)

Anderson, Brenda Carol 01 January 2015 (has links)
Reproductive biology is a necessary element for the management of elasmobranch fisheries. Traditionally, characterization of elasmobranch reproduction has involved lethal sampling to examine gross reproductive structures and development of embryos. However, this method is counterproductive to the conservation of shark populations. One non-lethal alternative is the measurement of serum hormones, which often vary according to reproductive events. Radioimmunoassay (RIA) has been used to measure hormone concentrations in reproductive endocrinology, but can be problematic for researchers. Alternatively, chemiluminescence immunoassays (CLIA) are routinely used for measuring circulating hormone concentrations in low-volume, non-extracted human serum samples. However these assays have not been previously examined for use with elasmobranch blood. In the first component of this study, I examined whether CLIA was a suitable alternative for detecting seasonal profiles of these hormones in the bonnethead, Sphyrna tiburo. This was accomplished by collecting serum from sexually mature male (n = 35) and female (n = 32) bonnetheads , measuring reproductive organs for maturity and reproductive stage, and measuring concentrations of testosterone (T) in males, and 17β-estradiol (E2) and progesterone (P4) in females using RIA and CLIA. CLIA was successfully validated for use with shark serum by assessing parallelism and spike recovery. CLIA-derived measurements were significantly correlated with those obtained with RIA (r = 0.809, 0.773, and 0.908 for T, E2, and P4, respectively; p
246

Nutrient Transport by Shrimp Hepatopancreas

Simmons, Tamla A 01 January 2012 (has links)
Purified brush border membrane vesicles (BBMV) were isolated to characterize primary cellular transport mechanisms for white shrimp. The ultimate goal is to determine the effective components of a shrimp’s diet, thereby enhancing growth, as well as nutrient content. Juvenile shrimp are dependent on plant material as a food source. Potassium is a key component of plants, thus it may play a role in nutrient transport. In addition, divalent metals have been shown to act as co-transporters in several other organisms, thus they may serve as a transport mechanism for shrimp. Fresh, live, white or brown shrimp were obtained, and from them 15-30 hepatopancreases were dissected to prepare the BBMV. Methods for preparing BBMV were based on the Mg2+ precipitation technique developed by Kessler et al., (1978) and Biber et al. (1981) for mammalian eipithelia and applied to crustaceans. The results suggest that there is a sodium/potassium-dependent glucose transport system that resembles the SGLT1 system of vertebrates, except the shrimp transporter can accept both sodium and potassium as cofactors, while the vertebrate system is restricted to sodium stimulation. Potassium showed strong stimulation of L-histidine uptake by shrimp BBMV, suggesting that a crustacean isoform of the insect potassium-dependent carrier protein (KAAT1) might be present in shrimp, and contribute to amino acid uptake. Amino acids also appear to form bis-complexes with divalent metals, that are transported by an analog of the dipeptide transporter (PEPT1). The metals appear to be accommodated, with varying affinities. PEPT1 has been described as a very non-specific carrier process because it transports such a wide range of di- and tripeptide combinations.
247

The Reproductive Biology of the Finetooth Shark, Carcharhinus isodon, in the Northwest Atlantic Ocean

Brown, Amanda 01 January 2015 (has links)
Shark fisheries are a multimillion dollar industry in the United States and have significant contributions both recreationally and commercially. In order to maintain this industry, fisheries must be properly managed. An understanding of life history and reproduction is crucial in order to adequately manage shark fisheries. The finetooth shark, Carcharhinus isodon, is a member of the small coastal shark (SCS) fishery complex. It is found in Atlantic waters from South Carolina to Florida and throughout the Gulf of Mexico. This species has recently come under increased fishing pressure and has previously been overfished. New data is needed in order to properly assess the reproductive capacity of this species so that healthy populations can be sustained. This study evaluated the overall reproductive cycle of northwest Atlantic populations of C. isodon using composite variables of morphology, histology and endocrinology. Atlantic C. isodon were found to display seasonal reproduction with biennial reproductive periodicity with a 12 month gestation period and litters of 2-6 pups. E2 and T displayed similar patterns and were highest during gametogenesis. P4 did not show any discernible patterns. Estrogen receptors were found in developing follicles of gravid and non-gravid females, in the oviducal glands of non-gravid and early pregnant females and in the uterus of pre-ovulatory females. P4 was found in the oviducal glands in all reproductive stages and in the uterus of pre-ovulatory females. Androgen receptors were found in Sertoli cells and mature spermatozoa as well as epididymal epithelial cells.
248

The Vezo communities and fisheries of the coral reef ecosystem in the Bay of Ranobe, Madagascar

Abeare, Shane 20 December 2019 (has links)
Madagascar, a country whose extraordinary levels of endemism and biodiversity are celebrated globally by scientists and laymen alike, yet historically has received surprisingly little research attention, is the setting of the present dissertation. Here, I contribute to the need for applied research by: 1) focusing on the most intensely fished section of the Toliara Barrier Reef, the Bay of Ranobe; 2) characterizing the marine environment, the human population, and the fisheries; and 3) collecting the longest known time-series of data on fisheries of Madagascar, thereby providing a useful baseline for future analyses. In Chapter 1, the bathymetry of the Bay was characterized following a unique application of the boosted regression tree classifier to the RGB bands of IKONOS imagery. Derivation of water depths, based on DOS-corrected images, following a generic, log-transformed multiple linear regression approach produced a predictive accuracy of 1.28 m, whereas model fitting performed using the boosted regression tree classifier, allowing for interaction effects (tree complexity= 2), provided increased accuracy (RMSE= 1.01 m). Estimates of human population abundance, distribution, and dynamics were obtained following a dwelling-unit enumeration approach, using IKONOS Panchromatic and Google Earth images. Results indicated, in 2016, 31,850 people lived within 1 km of the shore, and 28,046 people lived within the 12 coastal villages of the Bay. Localized population growth rates within the villages, where birth rates and migration are combined, ranged from 2.96% - 6.83%, greatly exceeding official estimates of 2.78%. Annual pirogue counts demonstrated a shift in fishing effort from south to the north. Gear and boat (pirogue) profiles were developed, and the theoretical maximum number of fishermen predicted (n= 4,820), in 2013, from a regression model based on pirogue lengths (R2= 0.49). Spatial fishing effort distribution was mapped following a satellite-based enumeration of fishers-at-sea, resulting in a bay-wide estimate of intensity equaling 33.3 pirogue-meters km-2. Landings and CPUE were characterized, with respect to finfish, by family, species, gear, and village. Expansion of landings to bay-wide fisheries yields indicated 1,885.8 mt year-1 of mixed fisheries productivity, with an estimated wholesale value of 1.64 million USD per annum.
249

New England’s Underutilized Seafood Species: Defining And Exploring Marketplace Potential In A Changing Climate

Davis, Amanda 18 December 2020 (has links)
New England’s seafood industry has been searching for opportunities to diversify their landings and build resilience as it faces socio-economic challenges from a changing climate. Developing markets for underutilized species is one way the New England community could help their seafood industry build resilience. This thesis identified New England’s underutilized fish species and explored their marketplace potential by examining their availability in a changing climate, current availability to consumers, and consumers’ responses. In Chapter I, I account how New England’s seafood preferences have changed over time. In Chapter II, I identify New England’s seven underutilized seafood species: 1) Acadian redfish (Sebastes fasciatus), 2) Atlantic pollock (Pollachius virens), 3) butterfish (Peprilus triacanthus), 4) the Georges Bank and Georges Bank East stocks of haddock (Melanogrammus aeglefinus), 5) scup (Stenotomus chrysops 6) the northern stock of silver hake (Mercluccius bilinearis), and 7) white hake (Urophycis tenuis). In the same chapter, I show that climate change will likely affect the availability of these species differently and that the broader ecological and socio-economic responses from shifting distributions and phenology are largely unknown. In Chapter III, I demonstrate that besides haddock, underutilized species were rarely accessible to consumers in restaurants. In the same chapter, I show how resources would likely help consumers and restaurants connect with their underutilized species since popular seafood suggestion guides either overlook or provide inconsistent recommendations for all underutilized species. In Chapter IV, I suggest that younger generations (Millennials and Generation Z) are interested in engaging with underutilized species. These younger consumers responded positively to hake, haddock, and Atlantic pollock in sensory assessments. Finally, in Chapter V, I suggest how New England’s seafood supply chain can use results from this research to make more informed policy, marketing, and purchasing decisions that align with their sustainability goals. These insights into availability, access, and consumer response may help New England’s seafood industry strategize approaches that will connect younger consumers to their local seafood options and build new adaptive markets in a changing climate.
250

Cascades Island Lamprey Passage Structure: Evaluating Passage and Migration Following Structure Modifications

Lopez-Johnston, Siena Marie 05 December 2014 (has links)
Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are threatened severely by a lack of passage at mainstem dams, lamprey specific passage structures have been designed and constructed to address the problem. The Cascades Island Lamprey Passage Structure (LPS) at Bonneville Dam is the longest and steepest structure of its type, following the addition of an exit pipe which allows lampreys to travel from the tailrace of the dam to the forebay. The intent of this study was to assess lamprey use of the structure and whether the structure hinders lamprey migration to subsequent dams. The study was carried out during the 2013 migration season. The study used three different treatment groups of lampreys released on five dates spanning the migration season (n=75 lamprey). Two of these groups (n=50), with different tagging methods, were released directly into the LPS to assess passage success, travel time, and tagging effect. The third group (n=25) was released into the forebay to test whether the structure impedes migration upstream. Fish were monitored via receiver arrays on the LPS and at dams on the river system. Overall passage efficiency was 74% (37 of 50 used the CI LPS successfully). Mean travel time to navigate the structure was 12 h. Fish size had no significant effect on travel time in the LPS. Water temperature had a significant effect on travel time in the LPS. There was no statistically significant effect of tagging on passage efficiency or travel time. The groups that used the LPS performed slightly better migrating upstream to the next dam than the group that bypassed the structure, but the difference was not significant. The groups that used the LPS traveled to more subsequent dams upstream than did the group that bypassed the LPS. It can be concluded that lamprey passed the structure successfully. Temperature (proxy for seasonality) had an effect on travel time in the LPS; however fish size and tagging had no effect. The LPS does not affect the ability of migrating lampreys to continue migration to subsequent dams. Such findings have important implications for management of lamprey in the region.

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