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- ItemVariaciones de la abundancia numérica y biomasa del zooplancton de red en el Golfo San Jorge (año 1985)(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1987) Pérez Seijas, G.M.; Ramirez, F.C.; Viñas, M.D.A study was made on numercial and biomass variations of the zooplankton of the San Jorge Gulf (Argentina), based on samples from five cruises performed during 1985. The sampling was included within a proagramme for the biology and fishery evaluation of the shrimp Pleoticus muelleri. San Jorge, a large gulf of the northern patagonian shelf, comprises major fishery activities. Some fish species of economical importance depend on copepods for their feeding, like anchovy (Engraulis anchoita) or partially on middle-size plankters, like mackerel (Scomber japonicus). As a way for determining the trophic disponibility at the gulf, a study was made in order to express the numerical abundance of copepods, euphausiids and amphipods and other items of lesser importance, as well as their total biomass.
- ItemMetodología para definir alternativas de programación lineal. Parte 1: Utilización de un modelo de programación lineal(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1987) Bertolotti, M.I.; Abal, Horacio J.; Piergentili, G.V.; Vecino, M.S.The objective of this paper is to maximize a function of the value added of the Argentine fishery system, in order to provide alternatives for the management and development of the fishery sector.
- ItemAspectos generales de la pesca del bonito (Sarda sarda) en la Argentina(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1987) Hansen, J.E.Basic aspects of the fising of Bonito in Argentina such as: catch statistics, fleet and gears, season and fishing grounds, and catch per unit effort (CPUE) are analized. FAO World Catch Statistics show that none of the different populations of Sarda sarda or other species of the Genus may support a highly productive fishery Exceptions are Sarda chilensis and S.sarda from the Black Sea, which us exploited by Turkey. On the basis of available information it may be inferred that the Bonito of Argentina has more competitors and a narrower thophic spectrum than that from the Black Sea.
- ItemEstudios sobre el régimen alimentario del mero (Acanthistius brasilianus) y su relación con las características morfométricas del sistema digestivo (Pisces, Fam.Serranidae)(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1987) Goldstein, H.E.; Cousseau, M.B.Observations on the stomach content of the sea bass have been made in order to study the trophic spectrum and the feeding habits variations, according to the season, region and individual size. On the other hand, some morphometric and meristic characters of the buccopharyngeal cavity have been statistically analyzed in relation with the total length and compared with size and shape of the preys. The following characters were studied; length and width of the mouth; size of branchial arch; number and length of the gillrakers and distance between them.
- ItemObservaciones sobre el ciclo reproductivo del mero, Acanthistius brasilianus (Serranidae, Pisces)(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1987) Dell'Arciprete, O.P.; Christiansen, H.E.; Diaz de Astarloa, J.M.The present paper deals with the study of the reproductive cycle of the sea-bass (Acanthistius brasilianus). Its main objective is getting some advance in the inderstanding of the gonad cycle of the sea-bass and the comprehension of its mode of reproduction. The study is emphasized on tahe females because it is thought that they permit a better analysis in this first stage of the reseach work. Some basic aspects, such as the anatomical and the histological description of the gonadas, the study of ovocyte maturation phases and the development of ovary maturity scales were into account. The gonad cycle was analized throughout the year by means of different approaches; histological analysis of ovary preparation and by following the statistical structure of percentage frequencies of ovocyte diameters, and those of the ovary maturity stages, and gonad indexes. The different phases of regression of the post-ovulatory follicles are also considered. Finally, the length at first maturity was calculated; and the spawning mechanism of this species is described.