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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.
11

Reef Fish Movements and Marine Reserve Designs

Farmer, Nicholas Alexander 15 May 2009 (has links)
Movement patterns and space use by mature fishes are critical in determining the effectiveness of marine reserves in conserving spawning stock biomass and/or providing biomass to adjacent fisheries through 'spillover'. Home range sizes, activity patterns, site fidelity and habitat preferences were determined for acoustically-tagged snappers and groupers using a rigorously-calibrated array of omnidirectional hydroacoustic receivers deployed in the diverse coral reef environments of a no-take marine reserve (NTMR) network in the Dry Tortugas, Florida. An individual-based localizing tendency model of reef fish movement was parameterized from fine-scale acoustic telemetry data and integrated into a Spatial Management Performance Assessment (SMPA) simulation model for reef fish populations developed to quantitatively evaluate performance of no-take marine reserves in the Dry Tortugas, Florida. Spatially-explicit SMPA models were parameterized for three overfished stocks in the lucrative snapper-grouper fishery: red grouper (Epinephelus morio), black grouper (Mycteroperca bonaci), and mutton snapper (Lutjanus analis). SMPA models were used to evaluate the impacts of a variety of life histories, movement strategies and speeds, and management regulations upon long-term stock sustainability, as measured by annual changes in spawning potential ratio (SPR), and long-term stock productivity, as measured by annual changes in fisheries yield-in-weight per recruit (Yw/R). Under assumptions of constant regional fishing pressure, constant recruitment, and 'realistic' fish movement, SMPA simulation runs from initial conditions in 2000 suggested that by 2014, the Tortugas NTMR network should function to restore red grouper populations to 30% SPR, a Federal management benchmark for sustainability. Mutton snapper were the most mobile of the species investigated; if mutton snapper movements are ignored, their population is predicted to attain 30% SPR by 2014, but given 'realistic' mobility, they may not attain this target by 2021 without additional protections. Black grouper are currently fished at over 9 times sustainable levels. SMPA simulations suggest coupling an increase in minimum size at capture of 20 - 25 cm with NTMR implementation would result in substantial short term losses in yield, but would restore both black grouper and mutton snapper populations to 30% SPR by 2021 and lead to increased long-term yields. Although marine reserve sites are often chosen opportunistically, these findings strongly suggest that reserve designs (e.g. proper sizes and configurations) must take into account the scales and patterns of movement exhibited by the exploited stocks they are intended to protect. These modeling efforts also suggested reserves are not a panacea; in order to promote sustainability for severely depleted stocks, they must be accompanied by an overall reduction in fishing capacity. Although important questions remain concerning the movements of reef fish in response to habitat and density dependent processes, our analyses of realistic reef fish behaviors suggest that the NTMRs of the Dry Tortugas promote substantial gains in SPR, promoting long-term stock sustainability and enhanced egg production. Increased rates of movement diminish these benefits, but may also mitigate short-term losses in yield associated with NTMR establishment.
12

Waves of Change? Politics of Knowledge and Participation in Marine Protected Areas

Gray, Noella Jayne January 2009 (has links)
<p>Marine protected areas (MPAs) are an increasingly prevalent and popular conservation tool, yet there is still much debate over whether they should emphasize the role of expert knowledge or local participation. This debate occurs among an international network of scientists and conservation professionals as well as in relation to particular places and MPAs. This dissertation contributes to an understanding of MPAs by addressing three questions: (1) How do differently situated actors within the MPA social network define and mobilize ideas of knowledge and participation? (2) How are knowledge and participation enacted and perceived in particular MPAs? (3) How do perceptions of knowledge and participation relate to actors' views of the success of MPAs? In order to address these questions, this dissertation presents the results of two separate projects: (1) a survey of international experts at the First International Marine Protected Areas Congress; and (2) an ethnographic study of two marine protected areas and their associated communities and social networks in southern Belize. The results of the survey indicate that the international MPA community is divided in their opinions on what constitutes science and what role scientists should play in the MPA policy process. Scientists who had a positivist view of science were reluctant to engage in MPA policy making, whereas government representatives who held positivist beliefs were more likely to support scientists advocating for particular MPA policies. The results of the ethnographic study in Belize illustrate that multiple groups work to produce, interpret, and contest knowledge for MPA policy, while also engaging in scalar strategies to define what MPAs are, how they should function, and who should be involved in their management. MPA success in Belize is not dependent on either conclusive expert knowledge or positive perceptions of participation, but rather on the accommodation of multiple groups' agendas.</p> / Dissertation
13

Planning for Marine Protected Area - Case Study for Guishan Island

Shen, Cheng-Han 17 February 2011 (has links)
With the rapid development of the coastal environment and advances in fishing technology, marine biodiversity and fishery resources are decreasing dramatically. Therefore, each state is now focusing on conserving the marine environment. Planning Marine Protected Areas is one of the simplest and most efficient ways to do this. In recent years, researches have been conducted on Marine Protected Areas around the world. The government and academic fields in Taiwan also has started to value its surrounding marine environment. However, literature on the Marine Protected Areas in Taiwan has focused on policy and management, not so much on planning and zoning strategies. Therefore, this study uses the Geographic Information System (GIS) to simulate the planning and zoning process. This research set principles and zoning framework for Marine Protected Areas in Taiwan based on case studies and spatial analysis techniques. This study uses Gueishan Island in Yilan County as case study since the unique geographical environment of Gueishan Island provides potentiality to set Marine Protected Areas. In this study, it is suggested that "hot spring resources", "cetacean resources", and "fisheries resources" are the main protected objectives. The zoning strategies, management guidelines and recommendations are provided in this study based on these three protected objectives. According to the GIS simulation process, using the spatial analysis techniques is one of the possible efficient methodologies to plan and zone the Marine Protected Areas. With supplementary data and information, the results can be discussed more specifically in the further study. In addition, techniques of visualization during the MPAs zoning process can be a easier way for various stakeholders to understand, and to strengthen mutual communication, thereby reducing disputes to create successful Marine Protected Areas.
14

Studies on the Management Issues Related to the Establishment of Four Southern Islands as a Marine Protected Area and Its Comparison with Other Protected Areas in Penghu

Yeh, Chia-Yu 14 July 2011 (has links)
The protection and biodiversity of marine ecosystem become major concerns in the world. Taiwan is also increasingly interested in the establishment of marine protected areas, but it still lack of the scheme on ¡§how to perceive the process for the protected areas¡¨. The establishment of a protected area is all by the top down without a full planning for a proper managed mechanism, evaluation and assessment to the site. The lack of the funds from the government often causes the failure of monitoring and restoration to the protected site. These problems have caused unprovent from imappropiate management to the established protected areas or have made the protected site as a paper park by the administration. This study searches the literatures with regards to the planning processes and the site selection process of marine protected areas in Canada and Australia. The objective of the present study is initiated to determine and survey the problems of marine protected area (MPA) planning in Taiwan. The select sites for the present studies are the proposed MPA site ¡§Four Southern Island¡¨ and other established MPA sites in Penhu. The approaches for assessing the sites include the geographic information system (GIS) spatial analysis method for the aquatic resources and their distributions. Data collections consist of the funding sources for managing the MPA sites and the proposed planning for the delimitation of MPA at the shore areas. The biological information around the sites was assessable for the evaluation process in addition to the management scheme in the future requirement at the Four Southern Islands site. The current expanses supported by the Penhu county government and the Executive Yuan Coast Guard was used for comparing with the proposed budgets needed for the MPA sites. The results showed that the Four Southern Islands has not met with the requirements and guidelines as a MPA due to the lack of scientific survey on the distributions of aquatic species within the proposed 3 nm delimitation. A long-term research and monitoring of the resources shall be performed to evaluate the sites prior to be announced as a designate MPA site. Although local residents agreed positively about the important of MPA site establishment through the questionnaire and interviews, there is still the need to improve management practices and more strict law enforcement capacity to ensure the protection of the marine environment for achieving a sustainable development. The survey results have been made to the process of site selection of marine protected areas according to Canada, suggesting that the current planning of the Four Southern Islands in Penghu does not match the site selection process. There need to be clarified with the details of the implementation process. In the end, above finding may impact the establishment of protected areas, including the relationship between public sector¡¦s responsibilities, and socio-economic conditions of the surrounding area development, marine environment and resources and fishing activities and other aspects of the integration considerations. These are expected to be the important conditions for the recommendations for the MPA site selection and to ensure the sustainable development of marine environment.
15

Regional Analysis of Seafloor Characteristics at Reef Fish Spawning Aggregation Sites in the Caribbean

Kobara, Shinichi 2009 December 1900 (has links)
Overfishing of stock and decreasing biodiversity are grave concerns for the U.S. and the rest of the world. Understanding and applying spatial and temporal information of marine species’ reproductive ecology and critical life habitat is vital to the development of effective strategies for marine resource management. In the Caribbean, one of the critical science gaps hindering effective management is the lack of information on how environmental factors may make fish spawning aggregation (FSA) sites optimal for spawning. Understanding the patterns of seafloor characteristics of spawning aggregation sites is of great interest to managers who need a means to efficiently design marine protected areas to help rebuild regional fish stocks. The specific goals of the study were: (1) to map the seafloor at historically known grouper and snapper spawning aggregation sites in three different countries, and (2) to characterize quantitatively the geomorphology of the sites including horizontal and vertical curvature profiles of the reefs, bottom depth at spawning sites, distance between spawning sites and shelf-edges/reef promontory tips, and the shortest distance between the spawning sites and 100 m water depth. These data were field-collected with a GPS and single-beam eco-sounder that provided latitude/longitude and depth. The point data were interpolated to surfaces in GIS to determine slope, aspect, curvature, and distance from spawning sites and three-dimensional reef structures. This study revealed that all 12 known Nassau grouper spawning aggregation sites in Belize and 5 known sites in the Cayman Islands were located at convex-shaped seaward extending reefs (reef promontories) jutting into deep water, within 1 km of reef promontory tips. However, spawning aggregations did not always occur at the tips of reef promontories, though all were found along the shelf edges within 1 km of promontory tips. Sixteen sites were multi-species spawning sites. These general characteristics were used to predict an undiscovered multi-species spawning aggregation in Belize. A successful prediction in Belize, together with the compiled data from multiple sites indicate: 1) reef promontories are vital locations for transient reef fish spawning aggregations, and 2) this study provides a potential tool for prediction of unknown spawning sites in the Caribbean.
16

Spatial analysis modeling for marine reserve planning¡Ðexample of Kaomei wetland

Chen, Chun-te 16 July 2008 (has links)
It is an internationally acknowledged that marine protected area (MPA) is an important measure for maintaining biodiversity and rescuing endangered species. MPA can also effectively inhibit human interferences such as development and pollution discharge. The establishment of MPA is possible to fulfill the goal of sustainable management, which is to conserve marine habitat for an integrative ecosystem and a higher biodiversity. However, how to design an effective MPA remains an important research issue to be explored. In order to grasp the spatial distribution of the ecological data in the study area, the current research uses spatial interpolation tool, Kriging, provided by the Geographic information system (GIS) software. Then three spatial analytical models have been developed based on integer programming techniques. It is guarantee that all three models can find the global optimal solutions for the best protective area partitions. This quantitative approach is more efficient and effective compared to the qualitative methods in many aspects. The models are able to preserve the maximum ecological resources under the limited spatial area. Besides, the model formulation can be adjusted from different environmental impact factors to fulfill the requirements of users. The case study of the research is to design a MPA for Kaomei wetland. However the spatial analytical models developed in this research can also be applied to protected area design in land area.
17

Acoustic Monitoring of Scotian Shelf Northern Bottlenose Whales (Hyperoodon ampullatus)

Moors, Hilary B. 26 June 2012 (has links)
An important step for protecting Endangered species is the identification of critical habitat. This can be especially challenging for deep ocean species. Northern bottlenose whales (Hyperoodon ampullatus) are deep-diving beaked whales of the North Atlantic. A population of this species occurs along the edge of the Scotian Shelf primarily in three submarine canyons that have been identified as critical habitat for the population: the Gully (the largest submarine canyon off eastern North America), Shortland Canyon and Haldimand Canyon. The Scotian Shelf population is considered Endangered mainly due to its small numbers and the anthropogenic threats it faces. The primary objective of my research was to further identify critical habitat of the population using passive acoustic monitoring, increasing knowledge of how the whales use the canyons and adjacent areas throughout the year. A review of the literature on cetacean associations with submarine canyons indicates that various mechanisms may act to attract cetaceans to these features. While many different species occur in canyons globally, they appear to be particularly important habitat for beaked whales. I developed an automated click detection algorithm customized for detecting northern bottlenose whale echolocation clicks, and long-term acoustic recordings were analyzed to examine the presence and relative abundance of northern bottlenose whales on the Scotian Slope over various spatial and temporal scales. The whales occurred in the area consistently throughout the year and all three canyons, as well as the area between canyons, appeared to be important foraging grounds for the population. The whales displayed diurnal foraging patterns. I also investigated niche separation between northern bottlenose whales and sperm whales (Physeter macrocephalus), another deep diving species. The presence of the two species was positively correlated over all spatial and temporal scales examined. These results indicate that areas within and adjacent to the Gully are important foraging grounds for northern bottlenose whales throughout the year. Furthermore, in addition to the canyons themselves, the shelf-edge areas between the Gully, Shortland and Haldimand canyons may constitute critical habitat for the whales. This research will be used to inform management measures relevant to the protection and recovery of this Endangered population.
18

A meta-analysis of the value of marine protected areas for pelagic apex predators

Dunphy-Daly, Meagan January 2015 (has links)
<p>A vast range of theoretical and empirical studies now suggests that MPAs can conserve marine biodiversity and, under some circumstances, increase fishery yields. However, despite the importance of pelagic apex predators to ecosystem function, the effectiveness of spatial management for the conservation of pelagic apex predator species is still unknown. I used fishery-dependent logbook and observer datasets to assess fishing effort and both the catch and size of pelagic apex predator species around five different MPAs. The US Hawaii-based deep-set or Atlantic pelagic longline fisheries fish the waters around these MPAs; both of these fisheries have experienced multiple management measures over time to protect species and maximize fishery yield. The MPAs selected for this study range in size, age, level of protection, and reason for establishment. I found that only two MPAs of the five appeared to be benefitting the pelagic apex predator species that I selected: the DeSoto Canyon and East Florida Coast MPAs, both in the Atlantic Ocean. The size of yellowfin tuna around the DeSoto Canyon MPA borders has increased over time, as has fishing effort. In contrast, the size of swordfish has decreased near the boundary of the East Florida Coast MPA, although the catch of swordfish has increased. The increase in catch of smaller swordfish was not a surprise because the East Florida Coast MPA was established around an area that is a nursery habitat for swordfish. These results are promising for the use of static MPAs for the conservation of pelagic apex predators, but three of the MPAs in my study did not show any indication of increased fishing effort, increased catch, or changes in pelagic apex predator size near their boundaries over time. Therefore, the characteristics of the DeSoto Canyon and East Florida Coast MPAs may provide a template for how to best design new MPAs for pelagic apex predators. Both of these MPAs were established with the specific intent of reducing pelagic apex predator bycatch, in areas where there were historically high catch rates. Both areas are relatively large (> 85,000 km2) and are also closed year-round. In combination, these characteristics may provide protection for pelagic apex predators.</p> / Dissertation
19

Designing marine protected areas that are ecologically representative and socially equitable

Kockel, Alessia 12 June 2018 (has links)
The overexploitation of coastal ecosystems continues to threaten global biodiversity and fisheries. This has prompted international conservation commitments, such as the Convention of Biological Diversity’s Aichi Target 11, to improve the coverage and integrity of marine protected area (MPA) networks worldwide. As reflected in Target 11, MPA networks need to be both ecologically representative and socially equitable. Systematic conservation planning (SCP) is an effective and efficient process for designing MPA networks to achieve biodiversity targets at minimal impacts to society. However, SCP has rarely been used effectively to develop MPA networks in developing nations. Three key challenges contribute to this ‘research-implementation’ gap: (1) SCP research concepts and tools are biased towards developed countries, (2) complete and high-quality datasets are lacking in developing countries, and (3) socioeconomic complexities and needs of stakeholders tend to be oversimplified. In working towards addressing these challenges, this thesis focuses on Sogod Bay as a Philippines case study to examine the following overarching research question “How can systematic conservation planning be applied as a framework for designing MPAs to achieve national biodiversity objectives in a manner that is socially equitable and accommodating to the needs of coastal communities?”. To help answer this question, the thesis addresses three research objectives: 1. Develop and document strategies for incorporating dimensions of equity (recognition, procedural, and distributive) for stakeholders and coastal communities in the planning stages of SCP. 2. Investigate how recognition and procedural equity can impact the systematic design of MPA plans in terms of biodiversity representation, spatial efficiency, and distributive equity for fisher stakeholder groups and communities. 3. Evaluate and compare MPAs designed using a SCP approach with more conventional planning approaches in terms of their impacts on representation and social equity. Objective one and two were assessed in Chapter two of this thesis. The findings of this chapter demonstrate how equity considerations can be integrated in the planning stages of SCP though consulting with local partners; integrating science-driven and participatory approaches; recognizing the key stakeholder groups of MPAs (recognition equity); engaging with representatives of each stakeholder group and community to inform MPA planning processes (procedural equity), and distributing costs of MPAs fairly across all stakeholder groups and communities (distributive equity). Additionally, the chapter demonstrates how inadequate inclusion of stakeholders and/or the variations between communities can disproportionately impact some fishers and communities more than others. Objective three was achieved through the findings of Chapter three, which investigated impacts on representation and equity from MPA plans derived under a SCP approach and two conventional planning approaches. MPAs planned and selected by communities resulted in inadequately representation and unfair distributions of costs across fisheries and community. A donor-assisted approach that used local knowledge to select MPAs resulted in a plan with near-optimal representation but was inequitable for fisheries and communities. The SCP approach was the only approach to produce a representative and equitable MPA plan, thus highlighting the utility of SCP for achieving the representation and equity aspects of Target 11. / Graduate
20

Evaluating the impacts of integrating fisheries and conservation management

Gall, Sarah Caroline January 2016 (has links)
Historically, the governance streams of fisheries and conservation management have run separately to one another, with little attempt at integration despite their similar goals. Efforts to integrate the two have increased as a result of their similarities and the potential benefits that may arise, but a requirement for additional research was identified to determine the effectiveness of this approach. This thesis therefore took an interdisciplinary approach, seeking to combine knowledge and methods from ecological, social and economic disciplines to provide a holistic evaluation of the potential for success. Marine Protected Areas (MPAs) were chosen as a management tool to evaluate for this purpose. Ecological research used underwater video methods to show that potting may be compatible with the conservation objectives of a multi-use MPA, but that this will depend on the level of impact and what is deemed ‘acceptable’ by regulators. An evaluation of social acceptance of MPAs using Q methodology stressed the importance of stakeholder engagement and transparency in decision making. Stakeholder acceptance can be facilitated by provision of clear evidence of the need for management, and of the benefits it may bring. Economic research evaluated the potential economic benefits of multi-use MPAs through quantification of change in quantity and value of landings for potting fisheries finding landings increased following MPA implementation. Finally, the thesis considered the effectiveness of ecosystem based fisheries management using a questionnaire designed to gather the opinions of stakeholders. This highlighted the potential role of co-management and the value of the ecosystem approach and emphasised the need for responsive, adaptive management which considers all stakeholders and all three disciplines. Overall the thesis highlighted the strength of taking an interdisciplinary approach, finding that whilst there is evidence for successful integration seen through designation of well managed multi-use MPAs, success may be limited by fundamental differences in the goals of the two streams. Further success may be facilitated by increased evidence for the benefits of integration for both governance streams, and provision of adequate resources to ensure management measures are reactive and adaptive.

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