881 resultados para Manutenção de stocks


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ENGLISH: The skipjack tuna, Katsuwonus pelamis is an important resource of the tropical and subtropical waters of the world ocean. Fishermen of many countries exploit this resource; at the present time, the annual world catch is approximately 200 thousand metric tons. Many fishery experts believe that the skipjack is not being fully utilized while stocks of other tunas are being fished, in some areas, at levels exceeding their maximum sustainable yields. In addition to the importance of skipjack as a commercial fish and as a source of food, there is a small but expanding recreational fishery in some countries bordering the Pacific. This bibliography provides a list of publications pertaining to the biology and fishery of the Pacific skipjack tuna. Papers concerned with food technology, food chemistry, radio-chemistry, and certain other subjects are excluded. The main sources for our publication have been the existing bibliographies of tunas, which are listed and indexed accordingly. In addition, reports of various marine laboratories and other scientific organizations have been checked; these are too numerous to list. We are fairly confident that all major works pertaining to skipjack tuna in the Pacific, printed prior to the end of 1966, appear in this bibliography. Only reports considered to be in permanent form are included. Annotations are based on actual examination of each of the entries listed here. The annotations do not evaluate a paper but serve rather to give a more precise idea of its contents if not revealed by the title alone. If the title sufficed in this respect, no annotation was prepared. A relatively small number of works believed to contain information pertinent to our bibliography could not be examined, but a list of such papers is provided. SPANISH: El atún barrilete, Katsuwonus pelamis, es un recurso importante de las aguas tropicales y subtropicales del océano mundial. Los pescadores de varios países explotan este recurso; actualmente, la captura mundial anual es aproximadamente de 200,000 toneladas métricas. Muchos expertos en la pesquería creen que el barrilete no es utilizado completamente, mientras los stocks de otros atunes son pescados en algunas áreas a niveles que exceden su rendimiento máximo sostenible. Además de la importancia del barrilete como pez comercial y como fuente de alimento, existe una pesquería pequeña recreativa que se está desarrollando en algunos países colindantes con el Pacífico. Esta bibliografía suministra una lista de publicaciones correspondientes a la biología y pesquería del atún barrilete en el Pacífico. Estudios referentes a la tecnología alimenticia, química alimenticia, radioquímica y ciertos otros sujetos son excluídos. Las fuentes principales correspondientes a nuestra publicación han sido las bibliografías existentes sobre atunes, las cuales están enumeradas y catalogadas de acuerdo. Además, se han examinado los informes de varios laboratorios marítimos y los de otras organizaciones científicas; éstos son demasiado numerosos para enumerar. Estamos bastante seguros de que todos los trabajos principales correspondientes al atún barrilete del Pacífico, editados antes de terminar el año de 1966, aparecen en esta bibliografía. Se incluyen únicamente los informes que se consideran permanentes. Las anotaciones se basan en el examen actual de cada una de las entradas aquí referidas. Las anotaciones no evaluan un estudio, pero sirven más bien para dar una idea más precisa de su contenido si el título por sí mismo no lo explica. No se preparó ninguna anotación si el título a este respecto era suficiente. Un número relativamente pequeño de trabajos que se cree tengan información pertinente a nuestra bibliografía no pudo ser examinado, pero se suministra una lista de tales estudios. (PDF contains 227 pages.)

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Balanço dos trabalhos realizados pelas 24 Subcomissões instaladas durante a 1ª fase da Assembleia Nacional Constituinte. Aprovação das propostas de fixação do tempo de 5 anos para o mandato do Presidente da República; criação do instituto do neoparlamentarismo no País; não intervenção do Estado na economia; manutenção do monopólio estatal na exploração de petróleo; criação de 6 novos estados brasileiros; realização de eleições diretas para Governador do Distrito Federal em 1988; definição da jornada de trabalho de 40 horas semanais para todos os trabalhadores, bem como estabilidade no emprego e participação dos trabalhadores nos lucros das empresas privadas; manutenção da responsabilidade das Forças Armadas na garantia da ordem e da soberania, assim como do serviço militar obrigatório. Metodologia de trabalho da 2ª fase de trabalhos constituintes.

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ENGLISH: Catches of skipjack tuna supporting major fisheries in parts of the western, central and eastern Pacific Ocean have increased in recent years; thus, it is important to examine the dynamics of the fishery to determine man's effect on the abundance of the stocks. A general linear hypothesis model was developed to standardize fishing effort to a single vessel size and gear type. Standardized effort was then used to compute an index of abundance which accounts for seasonal variability in the fishing area. The indices of abundance were highly variable from year to year in both the northern and southern areas of the fishery but indicated a generally higher abundance in the south. Data from 438 fish tagged and recovered in the eastern Pacific Ocean were used to compute growth curves. A least-squares technique was used to estimate the parameters of the von Bertalanffy growth function. Two estimates of the parameters were made by analyzing the same data in different ways. For the first set of estimates, K= 0.819 on an annual instantaneous basis and L= 729 mm; for the second, K = 0.431 and L=881. These compared well with estimates derived using the Chapman-Richards growth function, which includes the von Bertalanffy function as a special case. It was concluded that the latter function provided an adequate empirical fit to the skipjack data since the more complicated function did not significantly improve the fit. Tagging data from three cruises involving 8852 releases and 1777 returns were used to compute mortality rates during the time the fish were in the fishery. Two models were used in the analyses. The best estimates of the catchability coefficient (q) in the north and south were 8.4 X 10- 4 and 5.0 X 10- 5 respectively. The other loss rate (X), which included losses due to emigration, natural mortality and mortality due to carrying a tag, was 0.14 on an annual instantaneous basis for both areas. To detect the possible effect of fishing on abundance and total yield, the relation between abundance and effort and between total catch and effort was examined. It was found that at levels of intensity observed in the fishery, fishing does not appear to have had any measurable effect on the stocks. It was concluded therefore that the total catch could probably be increased by substantially increasing total effort beyond the present level, and that the fluctuations in abundance are fishery-independent. The estimates of growth, mortality and fishing effort were used to compute yield-per-recruitment isopleths for skipjack in both the northern and southern areas. For a size at first entry of about 425 mm, the yield per recruitment was calculated at 3 pounds in the north and 1.5 pounds in the south. In both areas it would be possible to increase the yield per recruitment by increasing fishing effort. It was not possible to assess potential production of the skipjack stocks fished in the eastern Pacific, except to note that the fishery had not affected their abundance and that they were certainly under-exploited. It was concluded that the northern and southern stocks could support increased harvests, especially the latter. SPANISH: Las capturas de atún barrilete que sostienen las pesquerías principales de la parte occidental, central y oriental del Océano Pacífico han aumentado en los últimos años; así que es importante examinar la dinámica de la pesquería para determinar el efecto que pueda tener sobre la abundancia de los stocks. Se desarrolló un modelo hipotético, lineal para standardizar el esfuerzo de pesca a un solo tamaño de barco y tipo de arte. Luego se usó el esfuerzo standardizado para computar un índice de la abundancia que pueda dar razón de la variabilidad estacional en el área de pesca. Los índices de la abundancia variaron mucho de un año a otro tanto en el área septentrional como en el área meridional de la pesquería, pero indicaron una abundancia generalmente superior en el sur. Se emplearon los datos de 438 peces marcados y recuperados en el Océano Pacífico oriental para computar las curvas de crecimiento. Una técnica de mínimos cuadrados fue usada para estimar los parámetros de la función de crecimiento de van Bertalanffy. Se hicieron dos estimativos de los parámetros mediante el análisis de los mismos datos, de diferente manera. Para el primer juego de estimativos, K=0.819 sobre una base anual instantánea y L∞=729 mm; para el segundo, K=0.431 y L∞=881. Estos se correlacionaron bien con los estimativos obtenidos usando la función de crecimiento de Chapman-Richards, que incluye la de von Bertalanffy como un caso especial. Se decidió que la última función proveía un ajuste empírico, adecuado a los datos del barrilete, ya que la función más complicada no mejoró significativamente el ajuste. Los datos de marcación de tres cruceros incluyendo 8852 liberaciones y 1777 retornos, fueron usados para computar las tasas de mortalidad durante el tiempo en que los peces estuvieron en la pesquería. Se usaron dos modelos en los análisis. Los mejores estimativos del coeficiente de capturabilidad (q) en el norte y en el sur fueron 8.4 X 10-4 y 5.0 X 10-5 , respectivamente. La otra tasa de pérdida (X), la cual incluyó pérdidas debidas a la emigración, mortalidad natural y mortalidad debida a llevar una marca, fue 0.14 sobre una base anual instantánea para las dos áreas. Con el fin de descubrir el efecto que posiblemente pueda tener la pesca sobre la abundancia y el rendimiento total, se examinó la relación entre la abundancia y el esfuerzo y entre la captura total y el esfuerzo. Se encontró que a los niveles de la intensidad observada en la pesquería, la pesca no parece haber tenido ningún efecto perceptible en los stocks. Por lo tanto se decidió que mediante un aumento substancial del esfuerzo total, más allá del nivel actual, la captura total probablemente podría aumentarse, y que las fluctuaciones de la abundancia son independientes de la pesquería. Los estimativos del crecimiento, mortalidad y esfuerzo de pesca fueron usados para computar las isopletas del rendimiento por recluta del barrilete, tanto en las áreas del norte como del sur. Para una talla de primera entrada de unos 425 mm, el rendimiento por recluta fue calculado en 3 libras en el norte y 1.5 libras en el sur. En ambas áreas sería posible aumentar el rendimiento por recluta mediante un aumento del esfuerzo de pesca. No fue posible determinar la producción potencial de los stocks del barrilete pescado en el Pacífico oriental, excepto para observar que la pesquería no ha afectado su abundancia y que ciertamente se encuentran subexplotados. Se concluyó que los stocks norte y sur pueden soportar un aumento en el rendimiento, especialmente este último. (PDF contains 274 pages.)

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Profit maximization in fishery protects cod of western Baltic Sea against overfishing – Only a theoretical approach? The frame for the management of fish stocks politically given contains – apart from ecological and social goals – also an economic goal, which is considered here in particular. From the point of view of fishery enterprises the main management goal for the exploitation of fish stocks is the maximization of profit. There are models for the yield optimization since long time. They are mainly used so far to optimize fishing mortality. Here the Beverton and Holt yield model was used. Apart from the optimization of fishing effort the model was used to optimize age of first capture and thus mesh opening. Starting point of the considerations is a given age group of a fish stock. If this age group is completely fished the yield obtained from this age group is maximized. The investigations show that the term overfishing is not exclusively linked as frequently assumed with a too large fishing mortality, but likewise with a mismatch of the mesh opening. For the calculated example Baltic cod data are used. At present the cod is caught far from reaching its mass optimum. Therefore, the profit of fishery enterprises can in the long term be considerably increased by the optimization of the mesh opening. During the conversion from the state of the art to fishing with optimised mesh sizes, however, a loss of profit has to be expected. The title of the paper sounds provocative. However, the stock of the Baltic Sea cod is better protected by a long-term maximum-profit oriented exploitation than by the precautionary approach applied now.

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Definição de estratégias por Líderes em torno da votação da proposta de reforma agrária. Metodologia do 2º turno de votação. Expectativa de manutenção de direitos sociais incluídos no texto constitucional durante o 1º turno. Proposta do Relator Bernardo Cabral de incluir o conceito de função social da terra na Carta Magna.

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Inexistência de acordo entre empresários e trabalhadores em torno da proposta da turno de trabalho ininterrupto de 6 horas diárias. Manutenção pelos Constituintes da prisão por ordem de autoridade judiciária competente.

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Since 1990 North-east Atlantic fish species – arctic cod, saithe, haddock, redfish and Greenland halibut – have been investigated by on-board observers on the German commercial trawler FMS Kiel. These investigations are part of the national data collection regulation established by the European Union in recent years. Collected data are basic data for the scientific assessment of these important fish stocks of the European fisheries. The results of the observed cruises are used by the Arctic Fisheries Working Group of the International Council for the Exploration of the Seas (ICES). Biological investigations were carried out in Norwegian waters and the Barents Sea (ICES Divisions IIa and IIb) on board FMS Kiel in January to March and in August/September 2004. This report presents results of these cruises and an overview about the general fishery situation in 2004.

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From 1993 to 2003 special surveys were conducted to analyse temporal and spatial aspects of the spawning activities of cod in the Baltic Sea. The ICES advice for cod in the Baltic Sea is based on yearly stock assessments of two separate stocks the western (SD 22 – 24) and the eastern stock (SD 25 – 32). Both stocks are characterized by different spawning seasons. The general progression of the maturity suggests that two types of development can be distinguished. In the western Baltic Sea (SD 22) the maturity development is temporal stable, with a relative short, main spawning period from March to April - spring spawner. In the Arkona Sea and Bornholm Basin the main spawning season starts in June and probably finishes in September - summer spawner. The proportion of spawners in summer is significantly higher than in spring in the Arkona Sea and Bornholm Basin. This again underlines the importance of the Arkona Sea for the reproduction success of the eastern Baltic cod stock. The analysis furthermore show, that the proportion of male spawners was significantly higher than the proportion of female spawners in all areas and the investigated months. This observation suggests that the reproductive success is only limited by the number of female cod which participates in the spawning process.

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Surveys were conducted to analyse temporal and spatial aspects of the spawning activities of cod in the Baltic Sea from 1993 to 2003. Part I of the article describes the general maturity development and the spawning activities in the western Baltic Sea, the Arkona Sea and the Bornholm Sea. The studies suggest that two types of spawner can be distinguished, the spring spawner in the western Baltic Sea and the summer spawner in the Arkona Sea and the Bornholm Basin. The descriptive analysis is supported by statistical studies presented in this article. It is shown, that the proportion of spawning individuals is significantly higher in summer than in spring in the ArkonaSea and the Bornholm Sea. Furthermore, it is shown that reproductive mixing of both types of spawner is possible in the Arkona Sea in May/June due to the hydrographical conditions in the Arkona Sea which were suitable in 8 of 10 years for successful reproduction of both Baltic cod stocks, and that spatial expansion of spawning activities of the eastern Baltic cod stock into the Arkona Sea is positive correlated with the size of spawning stock in the Bornholm Sea.

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Cod, haddock, whiting, saithe, plaice, sole and Norway lobster are 7 main target species of the demersal mixed fisheries in the North Sea, Skagerrak and Eastern Channel. Gadoids and Norway lobsters are mainly taken in the nor-thern North Sea by towed gears except beam trawls while the flatfish fisheries are conducted in the southern North Sea mainly using beam trawls. Recently, the central North Sea appears less fished by demersal gears. Towed nets including seines and beam trawls equipped with meshes of more than 100 mm resp. more than 80 mm were identified as the main gears effecting the depleted cod and reduced plaice stocks. The saithe sector, using towed nets with meshes of more than110 mm, longlines, gill nets and others, appears to affect the 7 species to a lesser extend. These results support the interim effort limitations by gear types, vessel and month as enforced by the European Commission since 2003. TAC regulations alone are considered inefficient to sustainably harvest stocks by mixed fisheries. A fleet-effort management method is developed estimating the fleets’ effects based on the sum of partial exploitation rates of the species in mixed fisheries weighted by the ratio of the precautionary reference Bpa and the actual SSB size as ecological quality objective. Applying such fleet effort management could result in increased catch possibilities of some stocks by fleets selecting mainly few and non-overexploited stocks while respecting precautionary management constraints in minimum SSB or maximum exploitation rates at the same time.

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For many years the assessments of the commercially most important demersal fish stocks of cod, haddock, saithe, redfish and Greenland halibut have annually been carried out by the "Arctic Fisheries Working Group" of ICES. The most important results of the actual assessment are given in this report. It shows that the gadoid stocks of cod, haddock and saithe are in good and stable conditions and that the stocks are harvested within safe biological limits. The stocks of redfish and Greenland halibut are still at a low level and outside safe biological limits. Greenland halibut shows a slightly positive trend in spawning stock biomass, several year-classes and recruitment.