Assignment (MPhil)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Many species of tilapia such as Oreochromis mossambicus are euryhaline, able to adapt to different salinity waters. Their ability to withstand high salinity levels has given rise to the possibility of using tilapia as baitfish for tuna line fishery. The purpose of the study was to determine the survival rate of tilapia O. mossambicus during direct transfer from freshwater to the salinity levels of 0, 15, 20, 22.5, 25, 27.5, 30, 32.5, and 35 ppt. The data was analysed through means of univariate ANOVAand regression analysis. O. mossambicus showed no mortality to all salinity regimes up to 25 ppt. Mortality was observed at 27.5 ppt, with 100% mortality at 35 ppt. LC 50 and LC 90 were found to be 30.5 and 34.2 ppt, respectively. The results indicate that tilapia (0. mossambicus) will survive a direct transfer to salinities up to 25 ppt. acclimation will be required in the event of transfer to salinity levels above 25 ppt, in order to prevent significant levels of mortalities. / AFRIKAANSE OPSOMMING: Meeste van die tilapia spesies soos Oreochremis mossambicus het die vermoë om by water van verskillende soutgehaltes aantepas. Dit is hierdie vermoë om hoë sout vlakke te weerstaan wat die moontlikheid vir gebruik as lewende aas in die tuna langlyn visvangbedryf moontlik maak. Die doel van hierdie studie was om die oorlewingsvlak van tilapia, O. mossambicus te bepaal by die oorplasing van varswater direk na soutwater by vlakke van 0, 15, 20, 22.5, 25, 27.5, 30, 32.5, en 35 dele per duisend. Die data is verwerk deur gebruik te maak van eenvariant ANOVAen regressie analises. O. mossambicus het geen mortaliteite tot gevolg gehad by al die oorplasings van vlakke tot en met 25 dele per duisend sout nie. Mortaliteite is wel gevind vanaf 27.5 dele per duisend, met 100 % mortaliteite by 35 dele per duisend. LC 50 en LC90 was gewees 30.5 en 34.2 dele per duisend onderskeidelik. Die resultate toon aan dat tilapia (0. mossambicus) sal oorleef by direkte oorplasing na soutwater by vlakke van tot en met 25 dele per duisend. Tilapia wat na hoër vlakke as 25 dele per duisend oorgeplaas wil word, sal eers geleidelik moet akklimatiseer om mortaliteite te beperk.

Thesis (MBA)--Stellenbosch University, 1984. / BACKGROUND AND OBJECTIVE: The chief sector of the South African fishing industry, demersal trawling is in a state of uncertainty that brings its competitiveness and long term developnent into question. The Hake (Merluccius capensis and Merluccius paradoxus) resource, which accounts for 70% of the landed catch, has finally started on the expected road to recovery and it is anticipated that this will proceed shortly for a nunber of years. During 1983 comfort was derived from the resulting rise in catch per unit effort rates and a significant improvement in the average size of fish landed. This, together with lower fuel prices and increased operating efficiences, enable the industry to operate at lower expenditure. Unfortunately, a second successive reflection of the T.A.C. (Total Allowable Catch ) of 12% in 1983 meant that gains in productivity were not fully reflected in reduced landed costs. This year (1984) the T. A. C. was increased by 4,8% which only marginally improves the already poor situation. More serious difficulties can be traced to adverse market developments. The price of fish has fallen in real terms (see Table 1.1 below) over a number of years. However, in 1983, the industry experienced a startling fall in prices, the severity of which may be gauged from the fact that actual prices realised were roughly equal to those of 1981. (Bross, 8 May, 1984) This pattern is continuing through 1984 - as is seen in Table 1 .1, an extract from Irvin & Johnson financial results .

The main objective of this study was to estimate the demand for and value of Oregon ocean sport-caught salmon fishery. The primary technique employed to estimate the recreational demand was an aggregated zone average travel cost method (TCM). The willingness of an angler to pay was deduced from the estimated demand for recreational fishing. The concept of consumers' surplus was used in conjunction with the travel-cost based demand functions to estimate the net economic value of Oregon ocean sport-caught salmon. The net economic value computed for the pooled data from all ten ports was found to be about $6.4 million. This value was calculated based on the total travel cost per mile of one-way distance equal to 72 cents. The regional travel cost method (RTCM) was developed to measure the effects of substitutes and quality variables in the travel cost model. A system of a linear demand equations for the six larger ports was estimated by the seemingly unrelated regression equation (SURE) method. The substitute distances as proxies for substitute prices were found to be insignificant for this model. Likewise, attempts to include substitute distances using indexes constructed by the Principal Component analysis failed to give significant results, with the exception of Garibaldi and Brookings. The total net economic value for the regional travel cost model estimated by SURE was $9.1 million. The incremental value per coho equivalent was also assessed by using the relationship between catch and effort per month by port. The coho equivalent was constructed on the basis of average weights of the commercial salmon catch, which was roughly two coho to one chinook salmon. The weighted average incremental value per coho and chinook was found to be $23.46 and $43.17, respectively. These values were about 50 percent of their respective average values. A total of 66 out of 234 distance zones created had zero values. Tobit analysis was employed to efficiently estimate the recreational demand from this kind of data. From the estimated demand function, a net economic value of about $12.7 million was obtained. This value was higher than those estimated by the SURE method and the OLS in the simple model. It should be noted that all the above value estimates were based upon demand models that were not consistent with the theory of consumer demand. However, a theoretically consistent system of demand equations was estimated and presented in Appendix D. This model fitted the data better than the other models and should give more accurate estimates of consumer surplus. / Graduation date: 1989

The global fish population is declining. Aquaculture production is saturated and the global fish stock is operating at an unsustainable level. Genetically modified (GM) fish is a potential solution to relieve the natural fish stock, if the FDA grants the approval. The global fish population is harmed by environmental conditions and the inability for fish to adapt to changing conditions and human interactions. Genetic modification is a growing technology that has the ability to alleviate the fishing industry by modifying fish to grow faster, be disease tolerant, eat plant-based food, and be more nutritious. However, the approval process has been halted by complications in the approval process and government leaders responding to public fears and concerns of the safety of genetically modified fish. This thesis reviews the background of the fishing industry, concerns over GMOs, and analyzes the politics preventing the approval of GM fish. Lastly, this thesis recommends six approaches the FDA should mandate to reassure the public of the safety of GM fish.

Les pêcheries de thonidés représentent 7.9% de la production mondiale de produits de la mer. La plupart des stocks de thons sont pleinement exploités, et certains surexploités, et tous font face à une pression de pêche croissante. En raison de l'extension des zones de pêche, les évaluations des stocks dépendent en grande partie des captures commerciales. Toutefois, les données commerciales peuvent varier au cours du temps étant donné que les pêcheurs peuvent investir dans des engins de pêche et de l'équipement, s'établir au large des côtes, ou commencer à pêcher dans de nouvelles zones. Peu d'attention a été portée à la réponse des pêcheurs aux mesures de gestion ou aux conséquences de l'investissement technologique. L'objectif de la présente thèse est d'étudier les effets de stratégies de pêche et les réponses adaptatives des flottes de senneurs sur les thons tropicaux et la faune associée dans l'Océan Atlantic Est et dans l'Océan Pacifique Est. Dans un premier temps, nous montrons comment l'introduction de nouvelles technologies a eu un effet direct en augmentant la puissance de pêche, et un effet indirect en entraînant une modification des zones pêche. Nous étudions les effets de deux fermetures spatio-temporelles sur la dynamique de la flotte de senneurs européens. La première mesure de gestion a diminué les jours où des captures sont réalisées, les carrés avec capture à l'intérieur de la zone partiellement fermée, tandis que la pêche sur DCP a été redistribuée à l'extérieur de la zone et aucun changement n'a pas été enregistré pour la pêche sur banc libre. La seconde fermeture de pêche a entraîné une augmentation de toutes les activités de pêche en dehors de la zone. Dans l'Océan Pacifique Est, la flotte de senneurs mexicains a réagit à la fermeture d'une saison de pêche en diminuant le nombre de jours passés à quai. Par conséquent, le nombre de calées sur bancs associés aux dauphins a augmenté, et les niveaux de capture observés avant la mesure de gestion ont été maintenues. Nous analysons les effets des stratégies de senneurs de l'Union Européenne sur les prises accessoires. Nous mettons en évidence que la composition des espèces de requins capturés sous DCP et les raies capturées sur bancs libres ont changé au cours du temps. Nous estimons également que plusieurs types d'espèces peuvent être capturés par mode de pêche. / Tuna and tuna-like fisheries represent 7.9% of the global production of marine capture fisheries. Most tuna stocks are fully exploited and some overexploited, facing growing fishing pressures. Due to the extent of fishing grounds, stock assessments depend largely in commercial data, which vary over time because fishermen may invest in fishing technology, expand offshore, or start fishing in different areas. However, little attention has received the responses of fishermen facing management regulations or the effects resulting from technological investment. For these reasons the aim of this study was to investigate the effects of fishing strategies developed by purse seine fleets on tropical tunas and on associated fauna in the eastern Atlantic and eastern Pacific oceans. The continuous introduction of new fishing technology in the French fleet in the 1980s and the 1990s evidenced a direct increase in fishing power when large yellowfin in free-swimming school is targeted and likely an indirect effect by modifying the fishing grounds characterizing FAD-fishing on small size categories. The consequences of the two time-area closures on the spatio-temporal dynamics of the European Union fleet were investigated. The regulation on FADs resulted in a decrease in the days with catch and successful squares inside the restricted area, reallocating FAD-fishing outside the area while no change in free-swimming school fishing was observed. The no-take time-area increased all fishing activities outside the restricted area with apparently no gain in terms of protection of juveniles. In the eastern Pacific as a response to a closed season the Mexican fleet reduced days in port and consequently the number of sets on dolphin-associated schools increased, maintaining the catch levels observed before the regulation. The study of the effects of the EU fleet fishing strategies on bycatch over two time periods showed that the species composition of sharks caught on FADs and may be for rays caught on free-swimming schools changed over time. We also estimated the total number of species that can be potentially be caught by fishing mode.

The aim of this thesis is to analyze the current legal regulations of public guards and outline possibilities of its development de lege ferenda. This thesis consists of 7 chapters (including the introduction and conclusion), and these chapters are further divided into subsections. After the introduction follows chapter, which defines the basic concepts (public guards and environmental protection). The third chapter deals with the historical development of public guards. In the fourth, the largest chapter of this work is comprehensively described, analyzed and as knowledge of the practice confronted by applicable law of public guards. The following chapter deals with a brief insight into foreign legal regulations of environmental protection (France, Italy). The sixth chapter presents legal regulations de lege ferenda. In conclusion, there are actually assessed, identified and summarized considerations de lege ferenda.

Paper analyzes the EU legal regulation of fishing. Specifically, it focuses on activities and norms, aiming to make european fisheries become sustainable and environmentally friendly. The paper summarizes the development of the common fisheries policy (CFP), which is one of the EU sectoral policies. Emphasis is placed on latest reform of CFP, which aimed among other things to sustainability. The next part deals with individual management tools, which is controlled amount of inputs and outputs to / from the fishing process. To restriction of outputs (amount of fishery products) is used setting total allowable catches and quotas. To restriction of inputs is used reduction of fishing capacity of vessels, which given to the assign rights and available resources is excessive, and also by reducing fishing effort. In addition to these tools are an inportant technical measures serving to reduce the impact of fishing on marine ecosystems, and in particular the prohibition or restriction of non-selective and destructive fishing techniques, or delimitation areas or periods in whitch fishing is prohibited. Paper in addition to fishing rules also focuses on control regulation. Control of compliance and penalties for non-compliance are regulated in the EU control system for fisheries. This is designed to ensure...

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Oceanography in the Faculty of Applied Sciences at the Cape Peninsula University of Technology 2014 / The Tristan lobster Jasus tristani is distributed among several isolated islands and submerged seamounts in the South East Atlantic Ocean. This species occurs only at the Tristan da Cunha group, a British Overseas Territory and the World’s most remote inhabited island, and in international waters at Vema Seamount 1680 km ENE of Tristan. All these populations are exploited commercially. The catch, processing and export of J. tristani is the most important economic activity for the inhabitants of Tristan da Cunha, providing the livelihood of many families and accounting for approximately 80% of the Island’s revenue. Sustainable harvesting of this valuable resource requires accurate long-term data on catch and effort, as well as information on the most important biological parameters such as growth, recruitment, moulting and reproductive cycles. This information is critical for robust assessments and management strategies. This thesis describes the history of the lobster fishery at the Tristan da Cunha island group, reporting on catches and trends in Catch Per Unit Effort between 1967 and 2010. A total of 247,014 lobster samples, both sexes combined, was sampled for size composition and sex ratios, as well as 1,526 lobsters for length/weight relationships, between 1997 and 2010. This confirms earlier findings that females have broader and heavier tails than males for the same carapace length (CL). Results show that males dominate catches at all islands, and their average size was larger than that of females (83.5 ± 14.46 versus 73.4 ± 8.64 mm CL, respectively). Inter-island differences in lobster population structure appear to be caused by differences of food availability as well as in density-dependent growth and survival of young lobsters. The largest lobsters were found at Gough Island (87.2 ± 15.13 mm CL), and the smallest at Inaccessible island (73.2 ± 11.39 mm). Tristan was the next largest to Gough Island (84.0 ± 12.56 mm) followed by Nightingale island (78.2 ± 11.33 mm). Lobsters caught inshore were larger than those caught offshore, although this may be related in part to differences in catches between fishing gear types. This study showed that fecundity increases in a linear manner with CL, and although larger lobsters clearly produce more eggs than smaller ones, the gain in fecundity is not as great as in some lobster species where fecundity is more closely associated with weight. The study showed no significant differences in egg size between islands, or between large and small females at one island. The egg production per gram of body weight and mean egg diameter both seem to be less than reported in an earlier study in the 1990s. While it seems likely that this is due to differences in the way in which samples were collected (with only stage 2 ova collected and measured in this study), the possibility of a decline in fecundity needs to be investigated further. A range of management measures have been developed over the history of the fishery, and important current measures include an annual total allowable catch (TAC) for each island, minimum size limits, and a closed season timed to protect egg-bearing females. The fishery has recently been awarded certification by the Marine Stewardship Council. The study has confirmed that current conversion factors are broadly correct and that different size limits established for each island are justified. Concern is raised, however, by the fall in catch per unit effort and the mean size of lobsters at the three northern islands over the past 7 years. These trends will need to be closely monitored. There are still many uncertainties over key parameters such as growth and recruitment and the intention is to increase the knowledge base and our understanding of the dynamics of the lobster stock. A research plan has been developed, so that progress can be monitored through the gradual implementation of scientifically defendable fisheries management procedures and increased research and monitoring capacity.

A utilização dos produtos provenientes de elasmobrânquios é demonstrada desde os primeiros grupos que habitaram o nosso litoral. Pode-se afirmar estas relações com o estudo dos sítios arqueológicos denominados sambaquis, que foram utilizados pelos grupos de pescadores-coletores do litoral. Analisamos sete sambaquis localizados no litoral do Estado de São Paulo: sambaqui Maratuá, sambaqui do Mar Casado, sambaqui do Buracão, sambaquis Cosipa e sambaqui Piaçaguera (Baixada Santista), sítio Tenório e sítio do Mar Virado (Litoral Norte). Foram analisados 15.447 elementos faunísticos de elasmobrânquios, onde se identificou 16 espécies: tubarão-mangona - Carcharias taurus, tubarão-raposa - Alopias vulpinus, tubarão-branco - Carcharodon carcharias, anequim - Isurus oxyrinchus, Carcharhinus sp., tubarão-cabeça-chata - C. leucas, tubarão-fidalgo - C. obscurus, cação-baleeiro - C. plumbeus, tubarão-tigre - Galeocerdo cuvier, tubarão-azul - Prionace glauca, cação-frango - Rhizoprionodon sp., tubarão-martelo - Sphyrna tiburo, raia-serra - Pristis sp., raia-morcego - Aetobatus narinari, raia-sapo - Myliobatis goodei e raia-ticonha - Rhinoptera bonasus. Os grupos de pescadores-coletores utilizam os dentes, vértebras e ferrões dos tubarões e raias principalmente como instrumentos e adornos. A identificação de espécies de elasmobrânquios em sambaquis demonstra a relação e utilização destes pelo homem, conseqüentemente apresentando grande significância para vários grupos costeiros não só de nossa costa como em todas as regiões do mundo / The use of the originating products of elasmobranchs is demonstrated by them from the first groups that lived in our coast. It is possible to affirm these relations with the study of the archaeological so-called shell mounds, which were used by the groups of fishing-gatherers of the coast. We analyse seven shell mounds located in the coast of the State of São Paulo: sambaqui Maratuá, sambaqui do Mar Casado, sambaqui do Buracão, sambaquis Cosipa, sambaqui Piaçaguera, sítio Tenório e sítio do Mar Virado. 15.447 elements elasmobranchs faunal remains were analysed, where one identified 16 species: sandtiger shark - Carcharias taurus, thresher shark - Alopias vulpinus, white shark - Carcharodon carcharias, shortfin mako - Isurus oxyrinchus, Carcharhinus sp., bull shark - C. leucas, dusky shark - C. obscurus, sandbar shark - C. plumbeus, tiger shark - Galeocerdo cuvier, blue shark - Prionace glauca, sharpnose shark - Rhizoprionodon sp., bonnethead shark - Sphyrna tiburo, sawfish - Pristis sp., bat ray - Aetobatus narinari, eagle ray - Myliobatis goodei e cownose ray - Rhinoptera bonasus. The groups of fishig-gatherers use the teeth, vertebrae and spines of the sharks and you shine principally like instruments and adornments. The identification of species of elasmobranchs in shell mounds, it demonstrates the relation and use of this for the human being, consequently presenting great signification for several coastal groups not only of our coast I eat in all the regions of the world

No cenário da pesca artesanal nacional, a garantia de acesso aos territórios pesqueiros e a construção de cadeias produtivas que valorizem ao mesmo tempo o pescado e o pescador são condições que podem ser atingidas através da organização cooperativa da produção e das comunidades. O presente trabalho se pautou nas abordagens teórico-metodológicas da ação coletiva e da gestão compartilhada dos recursos de uso comum para analisar a trajetória de duas cooperativas em comunidades tradicionais pesqueiras no Brasil: a Cooperativa dos Pescadores Artesanais de Carutapera, no litoral das reentrâncias no Maranhão, e a Cooperativa dos Produtores de Ostra de Cananéia, no litoral sul de São Paulo. Foram realizados os seguintes procedimentos metodológicos: revisão bibliográfica, levantamento de dados secundários, observação direta dos fatos e fenômenos, contato com atores chave para fornecer dados e análise contextual dos estudos de caso. Os territórios onde se encontram cada uma das cooperativas foram descritos de acordo com os aspectos demográficos, sociais, econômicos e ambientais, servindo como ponto de partida para a compreensão do estado atual das áreas de estudo. As trajetórias das ações coletivas que levaram à criação das cooperativas foram sistematizadas em uma perspectiva histórica, separadas por fases e elencados os principais acontecimentos que contribuíram para o desenvolvimento do cooperativismo local. A análise desses dados permitiu inferir quais foram as dinâmicas chave na promoção da ação conjunta e coordenada entre os indivíduos. As cadeias produtivas locais foram descritas e as relações sociais de produção que regem os aspectos de mercado nessas cooperativas foram identificadas, assim como as bases de conhecimento tradicionais e ecológicos em que ocorre a produção nos sistemas pesqueiros. Por fim, descreveram-se as áreas de uso comum utilizadas pela pesca e maricultura artesanal e o funcionamento dos regimes de propriedade empregados na gestão desses territórios. A realização dessa pesquisa possibilitou a contraposição entre os dados de ambos estudos de casos em uma perspectiva de identificação de padrões semelhantes e divergentes entre as cooperativas estudadas. As principais contribuições foram no sentido de que é preciso atentar-se ao contexto que impulsiona o empreendimento das ações coletivas que almejam melhores condições de vida para as comunidades, buscando identificar as lideranças em potencial, os motivos que fazem com que as pessoas cooperem entre si e os mecanismos que mantêm a confiança entre os indivíduos, que por sua vez leva à retroalimentação desse ciclo solidário tecido nos atributos socioecológicos e em valores como a reciprocidade. / In the context of the Brazilian artisanal fishery, the assurance of access to fishing territories and the development of value chains that consider both fish and fisherman are conditions that can be achieved through cooperative organization of production and communities. This work is based on the theoretical-methodological approaches of the collective actions and the shared management of common-use resources, especially marine resources. That background was used to analyze the historical trajectory of two cooperatives in traditional fishing communities in Brazil: the Cooperative of Artisanal Fishermen of Carutapera, in the indentation of the coastline in Maranhão State, and the Cooperative of Oyster Producers of Cananeia, in the South coastline of São Paulo State. The following methodological proceedings were carried: literature review, secondary data collection, direct observation of facts and phenomena, contact with stakeholders for the provision of data and analysis of the study cases context. The territories where each cooperative are located were described according to demographical, social, economical and environmental aspects, as a starter for the understanding of the current state of the study areas. The trajectory of the collective action that had led to the creation of the cooperatives were organized in a historical perspective, separated by phases, and it was listed/organized according by the main events that had contributed to the development of local cooperatives. The analysis of the data allowed the inference of what were the facts and key phenomena in promoting of the joint and coordinated action among individuals. The local value chain was described, and the social relations of production that deal with the market aspects in these cooperatives, were also identified as well as the traditional and ecological knowledge in what had occurred the production in the fishery systems. Finally, it was described the common areas used for fishing and artisanal mariculture, and how the property regimes employed works in the management of these territories. The realization of this research allowed the opposition between the data from both case studies in an identification prospect of similar and divergent patterns between the studied cooperatives. The main contributions were to the effect that it is necessary to pay attention to the context that drives the development of collective actions. When aimed to better living conditions for the communities, it needs to identify potential leaders, the reasons that make people cooperate with each other and the mechanisms that maintain trust between individuals, which in turn leads to feedback that solidarity cycle fabric on values such as reciprocity.