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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.
1

The epibenthic colonization of artificial subtidal habitats at the Cape d'Aguilar Marine Reserve, Hong Kong /

Hawkins, Susan Terry. January 1998 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 206-229).
2

Protecting Biscayne: An Analysis of Strategies for the Protection of Biscayne National Park

Harvey, Janell M 04 November 2004 (has links)
Biscayne National Park is located off the southeast coast of Florida and attracts approximately half a million visitors annually. Managers of Biscayne National Park are proposing a new General Management Plan (GMP) in order to update the recreational and commercial use of resources in the park. A Fishery Management Plan (FMP) is also being drafted simultaneously in conjunction with the Florida Fish and Wildlife Conservation Commission in order to address concerns associated with management of fish stocks within the park. The proposed plan alternatives of the GMP and the recommendations of the FMP were developed in response to the negative impacts on the park's marine ecosystem due to exponential population growth of the adjacent Miami metropolitan area. Problems associated with decreasing water quality, habitat degradation, and species exploitation contribute to the diminishing integrity of resources in the park and surrounding area. Currently commercial and recreational fishing are allowed in most of Biscayne National Park. The National Park Service's proposed alternatives are highly complex in order to make an attempt at appeasing stakeholder interests. In addition the recommendations of the FMP join the GMP alternatives in omitting marine reserves, a management practice that is widely thought by the scientific community to be an important step in marine resource rehabilitation. At present, there is a noticeable absence of scientific information and lack of participation of scientists in management decisions. Biscayne National Park would ultimately benefit by incorporating marine reserves into the park, and adjusting them based on scientific studies conducted by an appointed Scientific Advisory Board. Partnerships with state, federal, and international agencies could promote the idea of being a part of a marine reserve network for optimal resource protection in the Caribbean. An increase in revenue from a permit system and entrance fees would also promote enforcement and protection of park resources. Simple but strong regulation in the park could also help alleviate enforcement problems. In addition education of park resource users should be expanded inside and outside the park.
3

Comparisons of Fish Species Inside and Outside of Marine Protected Areas off the South Central Coast of California

Rasmussen, David E 01 October 2010 (has links) (PDF)
COMPARISONS OF FISH SPECIES INSIDE AND OUTSIDE OF MARINE PROTECTED AREAS OFF THE SOUTH CENTRAL COAST OF CALIFORNIA David E. Rasmussen From 2004-2008 and 2008-2009 Cal Poly University researchers conducted two separate tag and recapture studies of nearshore fish populations along California’s central coast. Three locations were sampled that have experienced different degrees of fishing pressure. Big Creek MPA has been closed to all fishing from 1993 onwards and is the farthest from port of all locations. Cambria lies closest to port of the three locations and because of this has the highest fishing pressure. Piedras Blancas lies midway between Cambria and Big Creek. Portions of Cambria and Piedras Blancas were designated as MPAs in 2007. Sampling protocols of these two different studies differed in bait used and size of commercial fish trap. An experiment was conducted to simultaneously compare the different trapping and baiting protocols from the prior studies to find a conversion factor that related catch per unit effort (CPUE), length frequency distributions and captured fish diversity between the two studies, thus providing a means to connect the two data sets for stock assessments and baseline MPA monitoring. Our sampling showed no significant difference in mean fish length or diversity between the two protocols for the five most common nearshore fish species captured, and three of the five species showed no significant difference in CPUE. Cabezon (Scorpaenichthys marmoratus), showed a significantly lower CPUE (50.5%) using the MLPA monitoring protocols compared to the commercial fishing protocol and black and yellow rockfish (Sebastes chrysomelas) had a significantly higher CPUE (310%) using the MLPA monitoring protocol. These findings provide a means of maintaining data continuity across the entire sample region and inclusion of earlier projects in the analyses of nearshore fish populations of the region. With the linkage of these two studies we provide important baseline data for the Cambria MPA from before it was established in 2007. Fish populations were compared on a year-to-year basis within each location, and between the different locations. I found several main factors helped to explain differences in size and abundance across time within individual locations, and across the three locations. These factors were inherent differences in habitat, establishment of MPAs, and changes in fishing pressure and post-larval recruitment. Cabezon were largest within Big Creek, followed by Piedras Blancas and Cambria which held the smallest fish, suggesting that fishing pressure is influencing fish size. However, cabezon were more abundant at Cambria than either other location suggesting that location is influencing abundance. Within Cambria, we are seeing an MPA effect with abundance within the MPA staying stable while the reference site is declining. Gopher rockfish (Sebastes carnatus) and black and yellow rockfish had similar trends with size and abundance between locations. Big Creek and Piedras Blancas held the largest fish, while Cambria was smaller. Both rockfish species were most abundant at Big Creek, followed by Cambria then Piedras Blancas. Size for these species is likely influenced by fishing pressure, and abundance is likely influenced by both fishing pressure and location. Both species increased in abundance 2004-2009 at Cambria, and this could be due to improved levels of post-larval recruitment. There is also a possible MPA effect for gopher rockfish at Cambria with a near significant divergence in size of fish between the MPA and reference site. Kelp greenling (Hexagrammos decagrammus) were similar in size and abundance between all sampling locations. There is a possible MPA effect at Cambria, with a significantly higher abundance than the reference site; however this difference predates the MPA’s establishment but could have been exacerbated by it. Lingcod (Ophiodon elongatus) size did not vary significantly between sites, but they were the most abundant at Cambria, followed by Piedras Blancas, then Big Creek, suggesting that habitat is influencing abundance. There was also a possible MPA effect on abundance of lingcod at Cambria with the MPA having a significantly higher abundance than the reference site. Similarly to the kelp greenling, these differences predated the MPA, but could have been exacerbated by its establishment, and abundance within the MPA has stayed stable, while the reference site was declining. Big Creek and Piedras Blancas have similar Shannon-Weiner diversity values, while Cambria has significantly lower. However, after MPA establishment at Cambria, the MPA has attained significantly higher diversity levels than the reference site. Over the short period of time that the Piedras Blancas and Cambria MPA have been established the populations within them have changed. However, there are no discernable trends in size, abundance and diversity between the MPA and reference sites at both locations. It is likely that with these slower growing, long-lived fish species that it will take more years for differences between the sites to manifest themselves.
4

Marine Reserves with Fisheries Management: Regulations Aimed at People to Hit Biological Targets

January 2014 (has links)
abstract: Consideration of both biological and human-use dynamics in coupled social-ecological systems is essential for the success of interventions such as marine reserves. As purely human institutions, marine reserves have no direct effects on ecological systems. Consequently, the success of a marine reserve depends on managers` ability to alter human behavior in the direction and magnitude that supports reserve objectives. Further, a marine reserve is just one component in a larger coupled social-ecological system. The social, economic, political, and biological landscape all determine the social acceptability of a reserve, conflicts that arise, how the reserve interacts with existing fisheries management, accuracy of reserve monitoring, and whether the reserve is ultimately able to meet conservation and fishery enhancement goals. Just as the social-ecological landscape is critical at all stages for marine reserve, from initial establishment to maintenance, the reserve in turn interacts with biological and human use dynamics beyond its borders. Those interactions can lead to the failure of a reserve to meet management goals, or compromise management goals outside the reserve. I use a bio-economic model of a fishery in a spatially patchy environment to demonstrate how the pre-reserve fisheries management strategy determines the pattern of fishing effort displacement once the reserve is established, and discuss the social, political, and biological consequences of different patterns for the reserve and the fishery. Using a stochastic bio-economic model, I demonstrate how biological and human use connectivity can confound the accurate detection of reserve effects by violating assumptions in the quasi-experimental framework. Finally, I examine data on recreational fishing site selection to investigate changes in response to the announcement of enforcement of a marine reserve in the Gulf of California, Mexico. I generate a scale of fines that would fully or partially protect the reserve, providing a data-driven way for managers to balance biological and socio-economic goals. I suggest that natural resource managers consider human use dynamics with the same frequency, rigor, and tools as they do biological stocks. / Dissertation/Thesis / Ph.D. Applied Biological Sciences 2014
5

Suivi et évaluation de la pêche professionnelle au sein d'une Aire Marine Protégée : protocoles d'enquêtes et indicateurs de pression et d'impact. Application au Parc Marin de la Côte Bleue.

Leleu, Kevin 30 March 2012 (has links)
La surexploitation des ressources halieutiques a conduit à une crise majeure du secteur de la pêche professionnelle. Dans ce contexte, les pêcheries artisanales, et notamment les pêcheries aux petits métiers côtiers, apparaissent comme des modes d'exploitation potentiellement durables des ressources côtières. La diversité des engins utilisés et des espèces ciblées rend néanmoins complexe le suivi de cette composante importante de la pêche professionnelle. L'activité de pêche artisanale reste ainsi très peu évaluée en Méditerranée, et notamment à l'échelle d'une Aire Marine Protégée (AMP). Les AMP sont pourtant de plus en plus utilisées comme des outils de gestion de ces pêcheries, les effets des différentes mesures de gestion mises en place étant à même de bénéficier aux pêcheurs professionnels. A l'heure où le nombre d'AMP se multiplie, il apparaît alors nécessaire pour les gestionnaires comme pour les scientifiques de disposer d'indicateurs permettant de suivre l'activité de pêche professionnelle sur le territoire d'une AMP, et d'évaluer les effets de la gestion sur cette activité. Un protocole d'enquête pour le suivi de la pêche artisanale aux petits métiers côtiers a ainsi été mis en place entre juillet 2009 et juin 2010 au sein du Parc Marin de la Côte Bleue (PMCB), AMP méditerranéenne française comprenant deux réserves marines d'âge et de taille différents. Les données récoltées ont permis d'identifier sept métiers principaux pratiqués par les pêcheurs du PMCB, et de les caractériser par un groupe d'espèces cibles, un engin, un territoire et une période de pêche. L'effort de pêche et les captures ont alors pu être estimés à partir de ces métiers. / The overexploitation of fishery resources has led to a major fisheries crisis. In this context, artisanal fisheries, and in particular small-scale coastal fisheries, appear as relevant alternatives for a sustainable use of coastal resources. But the diversity of fishing gears and targeted species diversity make it difficult to assess this important component of the commercial fishery. Hence, the activity of small-scale artisanal fishing remains poorly known in the Mediterranean Sea and few studies focus on an assessment of this activity at the scale of a Marine Protected Area (MPA). MPAs are yet more and more used as management tools for these fisheries, as protection effects and targeted access regulations may benefit to commercial fishers. As many MPAs are going to be established in the short term, it seems necessary for managers and for scientists, to have indicators to monitor the artisanal small-scale coastal fishing activity within an MPA, and to estimate the effects of MPA management on this activity. A field protocol was defined and implemented between July 2009 and June 2010 within the Parc Marin de la Côte Bleue (PMCB), a French Mediterranean MPA including two marine reserves of different age and size. The collected data allowed identifying seven main métiers within the PMCB, and characterizing them by group of target species, type of gear, fishing grounds and fishing periods. Fishing effort and catch were estimated. In the Côte Bleue area, 3 512 fishing trips and 4645 fishing operations were performed by 30 active boats during the studied period, for a total of 10 300 km of immersed nets.
6

Estudio de la pesca artesanal en el entorno de la reserva marina de Cabo de Palos – Islas Hormigas. Estrategias de pesca, efecto de la protección y propuestas para la gestión

Esparza Alaminos, Oscar 19 November 2010 (has links)
Los objetivos de la tesis fueron estudiar los factores que pueden explicar la variabilidad existente en la distribución e intensidad de la pesca artesanal en torno a una reserva marina (RM), valorar el efecto de la protección sobre la pesca y analizar y valorar los efectos bio-económicos de configuraciones alternativas de diseño y gestión. Los resultados revelaron que las embarcaciones artesanales calan más artes, de menor longitud, en zonas de elevada diversidad de hábitats. El rendimiento pesquero depende del nivel de protección, la distancia a la RM y la diversidad de artes por unidad de área. La protección está teniendo resultados positivos sobre las poblaciones de peces explotadas y beneficiando a la economía local. El aumento de superficie protegida, distribuido en varias reservas integrales en emplazamientos adecuados, distanciadas unas decenas kilómetros, más que la reducción del esfuerzo, tendría efectos positivos sobre el poblamiento de peces y la economía local. / The aim of the present work is to study the factors that may explain the variability in distribution and intensity of artisanal fishing around a marine reserve, evaluate the reserve effect and analyze and assess the biological and economic effects of alternative configurations of a marine protected area. The results revealed that artisanal vessels used more fishing gears, but shorter, in high habitat diversity areas. The fishing yield depends of protection level, distance to marine reserve and diversity of fishing gears per unit area. The protection measures have had positive results on exploited fish populations and in the local economy. The increase of protected area surface, distributed on several no take zones at appropriate locations, a few kilometers apart, more than the reduction of the fishing effort, would have positive effects on the population of commercial fishes and the local economy.
7

Willingness to pay for marine-based tourism within the Ponto do Ouro Partial Marine Reserve, Mozambique

Daly, Clare Amelie Keating January 2014 (has links)
Marine and coastal ecosystems face widespread degradation largely because market failure hides the economic value of the goods and services provided by them. Marine protected areas (MPAs) can serve as a structure that ensures the continuing function of marine and coastal ecosystem goods and services. Yet, to be effective and sustainable, MPAs must be able to prove their economic worth and generate revenue. User-fees are a common system used to partially finance multi-use MPAs. This study applies contingent valuation as a method of economic valuation within an MPA in southern Mozambique. The objectives of this study are to determine the willingness to pay of combined user groups and of individual user groups for use of the Ponta do Ouro Partial Marine Reserve and to investigate the potential for the reserve to increase revenues for conservation through the implementation of a user-fee for marine based activities. The payment card contingent valuation method was employed to determine willingness to pay of dolphin swim tourists, scuba divers and fishermen. Data was collected by face-to-face interviews of 120 respondents within two popular tourist locations in the PPMR. Results show that visitors within the PPMR are mainly South Africans, loyal to the area. Probit and OLS regressions were used to determine the effects of various independent variables on willingness to pay. Results from the Probit model indicate that African residency, activity and environmental awareness were significant factors that influenced visitors being WTP more than R20 per person per day as a user fee within the PPMR. The OLS model examined independent variables that influenced visitors being willing to pay as well as the impact of the variables on the amount visitors were willing to pay. The OLS model found income, African residency and environmental awareness to be significant factors influencing visitors being willing to pay. The mean WTP was R43.75 per person per day. Using data supplied by the PPMR, conservative estimated annual revenues based on the implementation of this fee amount would range between R1.46m – R 3.3m.
8

Using Principles of Seascape Ecology to Consider Relationships Between Spatial Patterning and Mobile Marine Vertebrates in a Seagrass-Mangrove Ecotone in Bimini, Bahamas

Driscoll, Sarah Rebecca Taylor 07 May 2021 (has links)
No description available.

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