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Registros recuperados: 306 | |
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Fabré, N.N.. |
Los lenguados constituyen un importante recurso pesquero en el Mar Argentino. Más que en los volúmenes desembarcados (9 .731 t en 1991), esta importancia se centra en su elevado valor de comercialización debido a la alta calidad de su carne. Atendiendo a los desembarques totales realizados en el Mercado de Concentración Pesquera de Mar del Plata, los lenguados ocupan el octavo lugar. Estos desembarques están compuestos principalmente por especies de porte mediano a grande pertenecientes al género Paralichthys, y por ejemplares de tamaño mediano o pequeño de las especies Xystreuris rasile, y en menor proporción, Paralichthys isosceles. Este recurso es explotado, en el sector bonaerense, por las flotas de rada o ría y costera, mientras que la flota de altura... |
Tipo: Theses and Dissertations |
Palavras-chave: Geographical distribution; Population dynamics; Population structure; Growth; Reproduction; Mortality; Environmental effects; Ecosystems; Marine fish. |
Ano: 1992 |
URL: http://hdl.handle.net/1834/5158 |
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Ba, I.S.. |
Résumé: Cette étude traite de la biologie et de la dynamique des populations d’anchois (Engraulis encrasicolus) des côtes mauritaniennes. Après un bref rappel des conditions climatiques et hydrobiologiques de la région, une tentative de mise en évidence de race ou population locale a montré que cette espèce pourrait être rattachée à la population méridionale atlantique du Golfe de Gascogne. En Mauritanie, l’Anchois n’est pêché que de façon accessoire. Les captures les plus abondantes sont réalisées de mai à Septembre essentiellement dans la zone nord où l’on observe un upwelling permanent. Pour évaluer la taille du stock, des estimations de biomasse par échointégration ont été effectuées, mais celles-ci n’ont pas permis de donner un ordre de grandeur... |
Tipo: Theses and Dissertations |
Palavras-chave: Anchovy fisheries; Upwelling; Population dynamics; Mortality. |
Ano: 1988 |
URL: http://hdl.handle.net/1834/676 |
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Wöhler, O.C.. |
Length and age at first maturity was estimated, and the distribution of the spawning stock of castaneta (Cheilodactylus bergi) was analyzed, with the aim of understanding the spawning activity and its relation with oceanographic parameters. Samples came from two research cruises carried out in the Argentine-Uruguayan Common Fishing Zone (CFZ) (SW Atlantic, between 34 degree and 39 degree 30'S), during the end of spawning period (May-June) of 1991 and 1993. Length at first maturity was estimated in 21.34 cm and 23.69 cm of total length, for males and females respectively. Age at first maturity estimated for sexes combinated corresponding to 2.60 years. A spawning area in the north (between 35 degree and 37 degree S) was determined, showing a high incidence... |
Tipo: Journal Contribution |
Palavras-chave: Fishing grounds; Sexual maturity; Spawning seasons; Mortality; Environmental conditions. |
Ano: 1997 |
URL: http://hdl.handle.net/1834/5795 |
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Brown, D.R.; Leonarduzzi, E.; Averbuj, A.; Livore, J.P.. |
Argentine anchovy (Engraulis anchoita) eggs and larvae abundance distribution patterns in the Argentine northpatagonian littoral during January-April 2001 were analyzed. As the season progressed, a process of decline in the reproductive activity was observed. Larval growth and mortality rates were established. Age determinations were performed analyzing otoliths daily increments. The 0.43 mm day-1 growth rate average did not show space-time differences, fact attributed to the homogeneity of the thermal field. The 0.32 d-1 January natural mortality rate was determined by exponential decline. Mortality rates, estimated with the mortality-aggregation model, were considered dependent on the larval size. The value ranges (d-1) were 0.07-0.49, 0.05-0.61 and... |
Tipo: Journal Contribution |
Palavras-chave: Fish larvae; Growth; Otoliths; Mortality. |
Ano: 2013 |
URL: http://hdl.handle.net/1834/5500 |
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Gil-Agudelo, D.L.; Navas-Camacho, R.; Rodríguez-Ramírez, A.; Reyes-Nivia, M.C.; Bejarano, S.; Garzón-Ferreira, J.; Smith, G.W.. |
Los arrecifes coralinos, uno de los más bellos e importantes ecosistemas de nuestro planeta, han existido por más de 200 millones de años, sobreviviendo a grandes cambios durante su historia (glaciaciones, extinciones masivas, entre otros). Sin embargo, durante las últimas tres décadas se han registrado grandes y súbitos cambios en el medio marino que a juicio de algunos investigadores ponen en peligro la supervivencia de corales y arrecifes coralinos. Uno de los mayores problemas que enfrentan los arrecifes coralinos hoy en día es la aparición de enfermedades que atacan a los corales, la base de estos ecosistemas. No existe un concenso sobre si estas enfermedades son realmente nuevas o no, pero lo que sí se sabe es que algunas de ellas están creando... |
Tipo: Journal Contribution |
Palavras-chave: Coral reefs; Mortality; Coral reefs; Mortality; Http://aims.fao.org/aos/agrovoc/c_1880; Http://aims.fao.org/aos/agrovoc/c_4945. |
Ano: 2009 |
URL: http://hdl.handle.net/1834/3616 |
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Wöhler, O.C.. |
Length and age at first maturity was estimated, and the distribution of the spawning stock of castaneta (Cheilodactylus bergi) was analyzed, with the aim of understanding the spawning activity and its relation with oceanographic parameters. Samples came from two research cruises carried out in the Argentine-Uruguayan Common Fishing Zone (CFZ) (SW Atlantic, between 34 degree and 39 degree 30'S), during the end of spawning period (May-June) of 1991 and 1993. Length at first maturity was estimated in 21.34 cm and 23.69 cm of total length, for males and females respectively. Age at first maturity estimated for sexes combinated corresponding to 2.60 years. A spawning area in the north (between 35 degree and 37 degree S) was determined, showing a high incidence... |
Tipo: Journal Contribution |
Palavras-chave: Fishing grounds; Sexual maturity; Spawning seasons; Mortality; Environmental conditions. |
Ano: 1997 |
URL: http://hdl.handle.net/1834/5793 |
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Hansen, J.E.; Gru, D.L.; Perrotta, R.G.. |
An extensive area of the continental shelf -between 37°20' and 34°40'S - was reviewed through hidroacoustical methods in order to evaluate the anchovy biomass. Within the area of highest concentration, further data on anchovy abundance were recorded, and fish samples were taken. Large anchovy shoals were located at about 170 nm from Mar del Plata, mainly in zones with sharp changes in oceanographic conditions. The distribution of the species was not uniform, but "contagious", and the log-normal distribution provided the best fit for the echo-integrator recorded data. The biomass was estimated at 1,061,727 tons (Confidence limits in between 921,010 and 1,223,930 tons). Some parameters of the population were estimated, such as: lenght-weight relationship,... |
Tipo: Journal Contribution |
Palavras-chave: Length-weight relationships; Sex ratio; Age composition; Growth curves; Echo surveys; Mortality; Age composition; Sex ratio; Mortality; Http://aims.fao.org/aos/agrovoc/c_29093; Http://aims.fao.org/aos/agrovoc/c_7014; Http://aims.fao.org/aos/agrovoc/c_4945. |
Ano: 1986 |
URL: http://hdl.handle.net/1834/2038 |
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Jaramillo-González, J.; Acosta, A.. |
Los arrecifes coralinos del mundo han sufrido un declive durante las pasadas tres décadas. Estos cambios se han evaluado en arrecifes en franja; sin embargo, se desconoce si los tensores causantes de dichos cambios afectan la dinámica de una comunidad coralina en los primeros estados de la sucesión antes del desarrollo de un arrecife. Para resolver este interrogante, se monitoreó durante 2004, 2005 y 2006 una comuniddad coralina aislada en San Andrés. Se compararon temporalmente la abundancia, cobertura y mortalidad parcial sufrida por la comjnidad coralina y sus poblaciones de coral dominantes. La comunidad coralina no presentó variación estadística en riqueza, abundancia, cobertura, ni en área de mortalidad parcial. Sin embargo, esta comunidad si varió... |
Tipo: Journal Contribution |
Palavras-chave: Coral; Dynamics; Mortality; Mortality; Http://aims.fao.org/aos/agrovoc/c_4945. |
Ano: 2009 |
URL: http://hdl.handle.net/1834/3605 |
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Pappalardo, M.P.; Morsan, E.M.. |
In this study we analyze growth, mortality and estimated biomass trend of purple clam, Amiantis purpurata, population placed in Playa Villarino, (Northern San Matias gulf, Argentina) in the southern most boundary of its geographical distribution. Previously, the population structure was described composed by three consecutive cohorts settled among 1978-1980, and the individual growth rate showed high spatial variability. The hypothesis to test in this study is that growth rate is regulated by local biomass. We choice four sites with different densities, to assess growth rate, natural mortality and retrospective estimated biomass trend. During February 2003, densities and growth rate (using external growth bands measurements) were analyzed matching with a... |
Tipo: Journal Contribution |
Palavras-chave: Growth rate; Clam fisheries; Mortality; Growth curves; Density dependence; Biomass; Growth; Biomass. |
Ano: 2005 |
URL: http://hdl.handle.net/1834/4385 |
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Registros recuperados: 306 | |
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