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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.
251

The South African marine fisheries policy since 1994

Mbane, Nontuthuzelo Nosisa January 2004 (has links)
Dissertation (MTech( Public Management))--Cape Technikon, Cape Town, 2004 / Marine resources play a major role in sustaining the economy and social development of the nation and contribute to national economy, to employment and security of the local community. The South African fisheries management was conducted largel)' with political default. This denied most fishers access to marine resources. Since the democratic election of 1994, the government was left with the challenge to re-allocate rights in a way that would ensure that the under-presentation of historical disadvantaged individuals (HDl's) in the fishing industry would be corrected. The laws and regulations related to marine fisheries were also revised. The Marine Living Resources Act, No. 18 of 1998 attempted transformation in the fishing industry but lacked clear guidelines which led to litigation and crises in the fishing industry as many fishers were unhappy with the whole process. Marine fisheries policy was established and published in 1997 to address those historical imbalances by introducing the fishing right system of allocating rights to represent the national demographics of the country. This report seeks to describe the theory of the South African fishing industry, policy developments and the current status of permit allocation in South Africa. It will also examine the effectiveness in the implementation of the marine fisheries policy for South Africa. It will focus on the distribution of marine resources for commercial fishing purposes.
252

Comunidades aquáticas do reservatório de Serra da Mesa (GO): distribuição, influências e a pesca esportiva sobre o tucunaré azul (Cichla piquiti) / Aquatic communities of Serra da Mesa reservoir (GO): distribution, influences and recreational fishing on blue peacock bass (Cichla piquiti)

Silva, Leo Caetano Fernandes da 31 July 2013 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-18T12:47:22Z No. of bitstreams: 2 Tese - Leo Cartano Fernandes da Silva - 2013.pdf: 4204827 bytes, checksum: 32e2d37452b1a8310f2d6934fa94c0b5 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-18T12:49:04Z (GMT) No. of bitstreams: 2 Tese - Leo Cartano Fernandes da Silva - 2013.pdf: 4204827 bytes, checksum: 32e2d37452b1a8310f2d6934fa94c0b5 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-04-18T12:49:04Z (GMT). No. of bitstreams: 2 Tese - Leo Cartano Fernandes da Silva - 2013.pdf: 4204827 bytes, checksum: 32e2d37452b1a8310f2d6934fa94c0b5 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-07-31 / The objective of this work was explore the relationships between diet, morphology and taxonomy in 30 species from Serra da Mesa Reservoir. The relationships between diet and morphology, diet and taxonomy and morphology e taxonomy were examined using Mantel test. And we test the relationships between diet and morphology after retire the effect os taxonomy using Partial Mantel Test. We used RDA to explore relevant attributes to diet. Results show that, independently of Taxonomy, some of the trophic guilds could be grossly predicted from few relevant morphological attributes (i.e mouth width and mouth Height especially for piscivores and carnivores) and thus suggest a significant link between diet and morphology. In other words, species having similar diet tend to converge to some extent on some morphological attributes. / O objetivo deste trabalho foi explorar as relações entre dieta, morfologia e taxonomia de 30 espécies capturada no Reservatório de Serra da Mesa. As relações entre dieta e morfologia, dieta e taxonomia e morfologia e taxonomia foram testadas utilizando o teste de Mantel. E a relação entre dieta e morfologia, após retirado o efeito da taxonomia foi testada utilizando o teste de mantel parcial. Foi utilizada uma RDA para analisar quais características são importantes para as diferentes dietas apresentadas. Os resultados demonstraram que, independente da taxonomia, algumas guildas tróficas podem ser preditos a partir de alguns atributos morfológicos relevantes (i.e. altura e largura da boca para píscívoros e carnívoros) e sugere relação significativa entre dieta e morfologia. Ou seja, espécies que possuem dieta similar tendem a possuir características morfológicas semelhantes.
253

The status and prognosis of the smoothhound shark (mustelus mustelus) fishery in the Southeastern and Southwestern Cape coasts, South Africa

Da Silva, Charlene January 2008 (has links)
Global trends in commercially valuable teleost fisheries point to substantial deterioration in population size, offering limited potential for increased harvests. Consequently a shift in focus towards alternative fisheries has increased fishing effort towards targeting chondrichthyans as a possible solution to meet global demands. The life-history traits of chondrichthyans make them poor candidates for resolving economic and nutritional security as these make them particularly vulnerable to anthromorphic influences. Current fisheries management approaches based on centralized government intervention have proved inadequate. This failure of current management approaches is often linked with poor co-operation by industry with government when collecting fishery-dependent data. As management decisions are based on quantitative estimates from fishery assessment modes data collected are often of poor quality. Co-management with its implied power-sharing arrangement between government and fishing communities has been proposed as a more realistic alternative. The motivation within industry to collect high quality data can only be created with a feeling of ownership. The decline in linefish species in South Africa has led to increased exploitation of demersal sharks such as Mustelus mustelus. Their status as one of the target and by-catch species of South Africa's shark fisheries necessitated resource assessment. Age, growth, maturity and mortality calculations for M mustelus were made from data collected from 1983-2006. The maximum observed age for M mustelus was 25 years. Estimated von Bertalanffy growth parameters from observed length-at-age for combined sexes, females and males were L∞ = 1946.16 mm TL, K = 0.08 year⁻' , to = -3.63 year⁻'; L∞ = 2202.21mm, K = 0.05 year⁻', to = 4.67 years; and L∞ = 1713.19 mm TL, K = 0.08 year⁻' and to = -4.36 years, respectively. Instantaneous total mortality (Z) was estimated at 0.16 y⁻', whilst natural mortality (M) for M mustelus was estimated at 0.05 y⁻'. The age and length at 50% maturity was determined for combined sexes, females and males at 1216 mm TL corresponding to an age of 9.93 years, 1234 mm (TL) and 10.75 years, and 1106 mm TL and 9.1 years respectively. The smoothhound shark resource off the south-eastern and south-western Cape coast was assessed by three dynamic pool models; yield per recruit, spawner biomass per recruit and an extended yield and spawner biomass per recruit. Due to the longevity of elasmobranches the per-recruit model was extended over a 20 year time-frame to simulate resource responses to management options. Fo.1 was estimated as 0.034 year⁻' and F MAX was estimated as 0.045 year⁻'. FsB50 was estimated as 0.031. The extended per-recruit model tested the outcome of different management scenarios, Size and effort control showed the least probability of pristine biomass falling below 20% of current levels in 20 years (where selectivity was set at 3 years). The replacement yield model showed that the average catches over the past decade are 2.5 times higher than the replacement yield is on the South Coast and 1.30 on the West Coast. A more realistic level optimising yield would be at 0.05 with a selection pattern at 3 years, where the probability of the biomass falling to below 20% of pristine pre-exploited levels in twenty years becomes negligible. A comparison of the models showed that current catches need to be halved for exploitation of smoothhound sharks to be sustainable. The results of this study indicate a need for a management intervention for M mustelus in South Africa with regards to potential overexploitation and collection of quality data for further assessments. A demersal identification key was developed as part of this study, which should aid monitoring officials in accurately identifying shark logs for collecting data. This study showed how adopting a management plan with the inclusion of comanagement concepts would improve the quality of data collected and increase monitoring of fishing activities. The inclusion of co-management is possible due to the unique bottle neck created by few demersal shark processing facilities actively exporting shark. A fishery management plan was compiled proposing several management options including size and effort controls.
254

Aspects of the ecology and management of the Soupfin shark (Galeorhinus galeus) in South Africa

McCord, Meaghen Erica January 2005 (has links)
Global trends in teleost fisheries indicate significant population declines. Thus, alternative fisheries are being developed to meet the growing economic and nutritional demands of the expanding human population. Recently, it has been established that elasmobranch fisheries may fulfill these demands. As many elasmobranchs possess life-history characteristics that make them particularly vulnerable to overfishing, it is imperative to develop management strategies prior to the inception of these fisheries to ensure sustainable resource utilisation. In South Africa, elasmobranchs have been commercially exploited since the 1930s. Although generally considered an under-exploited resource, the potential for growth within these fisheries has been recognized. In 2005, the commercial shark fishery will undergo a transition from medium to long-term rights allocations. This represents an ideal opportunity for scientists and managers to develop precautionary species-specific management plans for commercially exploitable elasmobranch species. The soupfin shark (Galeorhinus galeus) is one of the principal target species in South Africa’s shark fisheries. Given its inherent susceptibility to overexploitation, G. galeus was selected as a management priority by South Africa’s regional fisheries organisation. The purpose of this study was to examine and describe the stock status of G. galeus in South Africa, and to develop a precautionary fishery management plan to ensure the sustainability of this resource. Age, growth, and mortality calculations for G. galeus were made from research survey data collected between 1996 and 1999. A small sample size precluded independent analyses of females. The maximum recorded age for G. galeus was 33 years. Estimated von Bertalanffy growth parameters from observed length-at-age for males and combined sexes were: L∞ 1542.8 mm TL, K 0.21 year⁻¹ , t₀ -2.79 year⁻¹ and L∞ 1560.3 mm TL, K 0.19 year¹, t₀ -3.03 year⁻¹, respectively. The age-at-50% maturity was determined to be 6 years, corresponding to 1011 mm TL for males and 1100 mm TL for combined sexes. Natural mortality was calculated as 0.126 yr⁻¹. The rate of instantaneous total mortality was calculated as 0.27 yr⁻¹. Catch trend analysis showed that catches and CPUE of G. galeus are increasing in the demersal longline fishery, and decreasing in the handline fishery. Decreasing catches and CPUE were observed in fishery-independent research survey data. The status of the soupfin shark stock was modelled using per-recruit analysis. The SB/R model indicated the soupfin shark is being optimally exploited and spawner biomass is at 43% of preexploitation levels. Current fishing levels ( F = 0.14 yr⁻¹) approximate the Fsb₄₀ level (F = 0.17 yr¹); thus, an increase in fishing pressure may lead to stock collapse. It was determined that the current age-at-capture (7.9 years) should be increased to 10 years, or 1420 mm TL, to maximize yield and minimize the possibility of recruitment failure. The results of this study indicate a need for immediate scientific and management intervention in South Africa’s soupfin shark fishery. An assessment report and fishery management plan for G. galeus was compiled, and several management options were proposed. These include the implementation of licence and size restrictions, as well as seasonal/area closures. The potential for an experimental gillnet fishery should be investigated.
255

Towards a new approach for coastal governance with an assessment of the Plettenberg Bay shore-based linefishery

King, Claire Margaret January 2006 (has links)
The overall aim of this thesis, as required by the funders, was to provide research that would contribute towards the development of a bay management plan, specifically information on the local fisheries. The thesis therefore includes an assessment of the local shore-based linefishery in terms of catch and effort and socio-economics, and the development of indicators from this information with which to assess the sustainability of the fishery. Finally an implementation strategy for an integrated coastal management approach for local resource governance is proposed The shore-based linefishery of Plettenberg Bay was assessed through a combination of roving creel and access point surveys which included questions aimed at the quantification of total effort, total catch and cpue, as well as the spatial trends in catch and effort. Angler demographics as well as opinions and knowledge of current fisheries regulations were obtained and the efficiency of the fishery inspectorate was assessed. The survey period extended from August 2003 to September 2004 during which 1189 angler interviews were conducted. Catch data obtained during this study was compared to catch data gathered during a research tagging program conducted in an area closed to fishing (Tsitsikamma National Park) and a semi-open area (Rebelsrus – Cape St. Francis), thereby highlighting differences in species composition, abundance and size distribution of certain species between areas of differing fishing pressures. The fishery surveys revealed that the shore-based fishery is primarily recreational (99%) and dominated by white males. Most anglers agreed with the current fisheries regulations (60%) and admitted to abiding by them, however when tested on the regulations of their target species, their knowledge was poor. Effort in the fishery was highly seasonal with peaks coinciding with major school holidays. Total annual effort was estimated at 102 566 angler-hours, with distinct spatial patterns in effort. Total annual catch for the Plettenberg Bay shore-based linefishery was estimated at 31 217 fish.year⁻¹ with a total mass of 13.6 tons. Thirty-six fish species (26 teleost species and 10 elasmobranchs species) were identified during the survey period with Blacktail Diplodus capensis, Strepie Sarpa salpa, Red tjor-tjor Pagellus natalensis, Shad Pomatomus saltatrix and Sand steenbras Lithognathus mormyrus being the five most commonly caught species. Only 32% of interviewed anglers were successful in catching a fish with just 22% catching their primary target species. In addition, a large proportion of the anglers (69%) reported a decline in catch rate, with most blaming the commercial sector as a reason for the decline. The overall catch rate was (cpue) 0.374 fish.angler.hour⁻¹ or 170 grams.angler.hour⁻¹, considerably lower than that obtained from the fishery exempt area (TNP = 1. 02 fish.angler.hour⁻¹) and the partially exploited area (Rebelsrus = 0.91 fish.angler.hour⁻¹). In terms of species composition the most obvious difference between the three areas was the low proportion of non-migratory reef-associated species like red roman, poenskop, John brown, santer and bronze bream in Plettenberg Bay. Size comparisons revealed that the majority of species (particularly reef-associated species) were larger in the TNP than both the semi-exploited (Rebelsrus) and exploited area (Plettenberg Bay). Collectively theses findings suggest that certain species have been locally depleted, that recreational fishing has impacted heavily on the fish stocks and that even partial closure or limited access to an area can offer protection. From the results key issues were identified and sustainability indicators proposed according to the three sustainability domains (ecological, institutional and social) proposed by Pajak (2000). Within the ecological domain the most pertinent issue was the low catch rate, particularly for reef-associated species. Indicators to track these issues included: percentage of successful trips (where fish were caught), percentage of anglers that reached their daily bag limits and the proportion of the overall catch that comprised larger, more desirable species. Institutionally the most pertinent issue was the apparent inability of management institutions to manage effectively marine resources within Plettenberg Bay. Indicators within this domain included the proportion of anglers who were inspected, the existence of a localised management plan and an associated monitoring programme. Socially the fishery proved to be fairly sustainable. Indicators included in this domain were the proportion of subsistence anglers in the local fishing community, the percentage of correct answers pertaining to current fishery regulations, the level of noncompliance and the percentage of undersize fish retained. Aggregation of all the indicators within a sustainability matrix revealed that the Plettenberg Bay shore-based linefishery was unsustainable and thus requires increased local management effort. Since there is no local management strategy in place, an integrated coastal management approach for the governance of the coastal resources in Plettenberg Bay has been proposed. The development of a Coastal Management Plan and a subsidiary Bay Management Plan provide the frameworks within which management strategies can be put into operation.
256

Fishing rights, redistribution and policy : the South African commercial T.A.C. fisheries

Mather, Diarmid John January 2005 (has links)
The main objective of this thesis is to provide an analysis of the economic logic behind fisheries policy and redistribution in South African. An examination of the institutional and organizational evolution reveals that South African fisheries policy followed the world trend in the movement toward quota management systems. However, it is argued that due to the peculiarities of the Apartheid political system, South Africa developed a unique and persistent structure of individual fishing rights that resulted in a transfer of power from the fisher to monopsonistic, and subsequently vertically integrated, fish processing companies. Problems, however, arose with the need to redistribute fishing rights to previously repressed racial groups. It is proposed that, within a specific form (TAC), the structure of individual fishing rights can be decomposed into four operational rules, namely, the right of participation, asset size, tradability and duration of term. Policy design is restricted to a feasible set of rules that impact on the flexibility of the system, the incentives facing private fishing companies and fishers, the efficiency of the fisheries management plan and finally the effect it has on a redistribution strategy. Within this analytical framework, South Africa's policy yields a very flexible system favourable to monopsonistic industrial organisation. However, by adding a redistribution constraint, this structure has a number of important effects. First, as new quota holders are added the information costs for effective fisheries management increase exponentially. Second, the transaction costs to private fishing companies are increased. Third, only the resource rent is redistributed (weak redistribution). Next, the micro to small vessel fisheries, the medium vessel fisheries and the large vessel fisheries are examined separately. The major aim is to determine, within the available data, the effect that a weak redistribution policy (redistribution of the resource rent), has on strong redistribution (redistribution of fishing capital and skills). The evidence definitely supports the analytical framework and suggests that fundamentally the structure of individual fishing rights, which evolved in response to a monopsonistic industrial organisation during the apartheid era in South Africa, works against strong redistribution. Also, that different fisheries face different constraints and that these should in certain instances be treated separately.
257

A development and management framework for a new Octopus vulgaris fishery in South Africa

Oosthuizen, Ané January 2004 (has links)
A new policy incorporating an operational protocol was developed for the establishment of new fisheries in South Africa. The common octopus, Octopus vulgaris was used as a candidate species for the project. The operational protocol consisted of a three-phased development framework, namely information gathering (Phase 0), an experimental fishery (Phase 1) and the final implementation of a commercial fishery (Phase 2). The present study focussed on phase 0 of this theoretical framework and protocol and was implemented by using a proposed octopus pot fishery in South Africa as a case study. Phase 0 included a desktop study, information gathering in the field, an economic feasibility study and the formulation of a Fishery Management Plan and experimental design for the fishery. Information gaps identified during the desktop study were addressed during field investigations into the population structure and biology of O. vulgaris along the southeast coast. Immature females were found to use the intertidal area to feed and grow before migrating to the subtidal area to mature and spawn. Mean size differed substantially between intertidal and subtidal areas, with larger octopus found subtidally. Age and growth trials using tetracycline as a marker showed that O. vulgaris deposit daily growth lines in their beaks. A genetic study showed that there is most likely only one panmitic population along the coast. The economic feasibility study indicated that a longline pot fishery could be feasible provided a 30% catch in 6600 pots/month is attained. Only existing, debt-free vessels should be used in this fishery. The Fishery Management Plan proposed in this study includes management measures such as effort limitation of licences and gear, size restrictions, vessel monitoring systems, and observer programmes. Based on the population dynamics and biology of O. vulgaris it is suggested that a precautionary approach to developing fisheries for this species in both the inter- and subtidal areas along the South African coast.
258

Examining News Coverage and Framing in the Context of Environmental Reporting: Using the Sea Lion and Salmon Controversy at the Bonneville Dam as a Case Study

McBride, Tess 01 January 2011 (has links)
This thesis examines how the construction of news stories reveals relationships among groups of stakeholders and how their views unfold within environmental conflict coverage. This study uses a content analysis of 161 newspaper articles concerning the sea lion and salmon controversy at the Bonneville Dam, focusing on source use and blame and solution frames in environmental conflict coverage. This analysis of articles published between January 2003 and June 2010 in Oregon, Washington, Idaho, California, and Montana contributes to research concerning journalistic norms (i.e., balance and objectivity) and news production routines, specifically within the field of environmental reporting. The findings indicate governmental sources were most frequently quoted and presented the most successful solution frames; while advocacy/non-profit sources were quoted less frequently (in addition to tribal sources) and presented the most blame and failed solution frames. Additionally, this research reflects on the role of news filters, including journalistic norms and legal issues, and explores the relationship between blame frames and failed solution frames, which is perhaps a reflection of the role of spokespeople and media jargon.
259

Graphical decision analysis of exploited fisheries

Hatton, Ian January 2003 (has links)
No description available.
260

Sampling characteristics of the bus route survey technique in the James River, Virginia

Stanovick, John Stuart 19 June 2006 (has links)
The bus route survey technique is a new on-site angler survey technique that was developed for small rivers, with remote access points and low angler use. The technique employs vehicle counts to collect angler effort information. Interviews are conducted at access points to collect user characteristic and catch data from arriving, mid-trip, or departing anglers. This technique was modified to sample total recreational use on 306 km of the James River from Glen Wilton to Richmond, Virginia. The river was spatially stratified into 6 areas, two urban areas (Areas 5 and 6), and four rural areas (Areas 1-4). The two-year study was conducted from March through November, in 1988 and 1989. In order to compare the bus route technique in a large riverine system, I conducted four 4-day intensive sampling days, two weekend and two week days, in Areas 1 and 4 during each year. During these periods a complete as possible access-point survey was conducted simultaneously with the bus route survey. Surveyors for both techniques collected effort, user characteristic, and catch data from several user groups. Aerial flights were also conducted to estimate effort during the 4-day intensive sampling periods. Effort estimates of the bus route and complete access-point surveys were similar in both areas, however aerial surveys collected 205 (29%) more hours of effort per sample because it included users accessing the river through undefined or private access points. Data collected on most user characteristics were not significantly different among methods. In three of four sampling periods catch was not significantly different between the bus route and complete access-point techniques, but in 1988, Area 4, catch was statistically higher for the complete access-point surveys. To solve this problem of underestimating case with the bus route survey more afternoon samples must be conducted to intercept departing anglers. In areas with more than 15 access points or driving time between access points is longer than half the survey day, the bus route can be extended over a two-day period, or a sub-sample of a number of access points can be surveyed. A 4-day intensive sampling period was conducted in 1989, Area 1 during the summer season to compare effort, user characteristics, and catch data between two-day, sub-sampling, and complete access-point surveys. Also, 26 sampling days were conducted in 1989, Area 1 during the summer season to compare effort, user characteristics, and catch between two-day and sub-sampling bus route techniques. No significant difference in effort, and certain (9) user characteristics, or angler catch data was detected between bus route modifications or the complete access-point survey. Also, no significant differences in effort, user characteristics (11), and angler catch variables (2) were detected between the two-day and sub-sampling methods that were conducted throughout the entire summer period. The bus route survey was designed to have equal daily probabilities. When unequal daily probabilities are used, the daily effort formula becomes complex. Daily effort, user characteristics, and catch data were compared from interviews conducted in morning and afternoon samples in 1989, Area 4 during the summer season. Results showed no statistical difference in effort although a mean of 72 (52%) more hours of effort were collected per afternoon sampling period. Most user characteristics were not significantly different, but a larger proportion of departing users were interviewed in the afternoon period (54%) then the morning period (22%). Because only two departing interviews in the early sampling period were anglers, catch estimates could not be compared between the two periods. If collecting catch data is an important survey objective, then more afternoon bus route sampling periods must be conducted. / Ph. D.

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