• Variaciones en la composición bioquímica proximal de la anchoíta durante tres temporadas de pesca (1975-1977)

      Moreno, V.J.; Aizpun, J.E.; Malaspina, A.M. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1979)
      Seasonal variations in major biochemical compoenets (lipids, protein and water)as well as in ash content of muscle and filletin remains of Engraulis anchoita were studied separately along three consecutive fishing seasons (May-December 1975, 1976 and 1977). Five to ten adult fish of each sex and of nearly identical length (total length: 160-165 mm)were selected at approximately monthly intervals from commercial catches at Mar del Plata Harbour. During the course of the three sampling periods, the proportions of the different biochemcial components showed a very similar pattern of variation and the difference from one fishing season to another never exceeded one month.
    • Ecología trófica de la caballa del Mar Argentino (Scombridae, Scomber japonicus marplatensis). Parte I. Alimentación y crecimiento

      Angelescu, V.A. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1979)
      The present study describes the morphology of the digestive system, the feeding and feeding behaviour, and the trophic relationships of the mackerel in the coastal waters regions, pelagic zone, along the Province of Buenol Aires. At the same time, this study is completed with a bioestatistical analysis on growth rhythm of body length and body weight of secondary juveniles, pre-adults and adults. All the biological information and statistical data correspond, only to the period november-march and the summer trophic habitat area.
    • Un modelo estocástico de pesquerías

      Gregorio, C.G.; D'Attellis, C.E. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1979)
      Based on the Schaefer production model, an stochastic model is described, that is a model in which noises perturbing biomass and measurements are considered, serving to describe random variations in mortality and recruitment as well as some inaccuracies in measurements taken. The model is discrete, linear and adaptable, and the parameters biomass and noises intensities are restimated with each new measurement obtained. The problem of regulation is solved, on the basis of the model described, through fishing effort that should be applied to keep biomasss close to equilibrium. Computer effected simulations are presented.
    • Reproducción y fecundidad del surel (Trachurus picturatus australis)

      Cassia, M.C.; de Ciechomski, J.D. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP, 1980)
      Studies on the sexual maturation on the jack mackerel in the area close to Mar del Plata were carried out throughout the whole year, 56 almost ripe females between 160 and 210 mm in total length and between 38 and 78 g is weight were taken into consideration for fecundity determinations. The most importante results obtained during these studies are the following: The gonad index was rather high and reached the value of 11.5.-The reproduction season is a rather one and the spawning occurs mainly in December and January.-It is assumed that a female of this species spawns once over a reproduction season, but shedding numerous batches of eggs in short intervals.-The lowest value found for the fecundity was 15.825 ovocites and the highest one was 82.892.-It is started that there exist great differences in the fecundity between the females within the same size and weight groups.
    • Nota sobre la consideración de retardos en un modelo de pesquerías

      D'Attellis, C.E. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1980)
      In the application of some techniques for the estimation and the regulation of fishery models with delays, it is necessary to have a validated linear model. In this note, we construct such a linear model using the Paunter approximation for delays.
    • Los recursos pesqueros demersales del Mar Argentino. Parte I. Evaluación de la biomasa (Standing stock)de la merluza común (Merluccius hubbsi)y de la merluza austral (Merluccius polylepis)en el área de su distribución estival

      Simonazzi, M.A.; Otero, H.O. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1980)
      The present paper deals with the standing stock (Pw1)of the common hake (Merluccius hubbsi)and the austral hake (Merluccius polylepis), using the swept are method (Alverson, 1971)and with the Potential Yield (Cmax)using the Gulland (1970)method. The standing stock of the common hake was 2.642.715 tons. the highest concentrations of this specie were distributed over 12.348 nm² (13 o/o of the toal distribution area)with 1.178.843 tons. This area was located between 41° and 45° of south latitude and between the coast and 100 m of bottom depth in the Patagonian Shelf. The other 1.463.872 tons were distributed over a wide area of 82.727 nm².
    • Fertilidad y periodicidad del desove en Ostrea puelchana

      Morriconi, E.; Calvo, J. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1980)
      Larvae production by Ostrea puelchana was studied in colections obtained from November to March 1977-78 and 1978-79. During the first period there seems to be a direct relation between the highest percentage of gravid female and the moon crescent quarter. This relation is not repeated in the following year. Compared with other larviparous oysters, O.puelchana produces a greather number of embryons of smaller size, with shorter breeding period and longer planktonic life.
    • Distribución, áreas de concentración y estructura de la población del bacalao austral (Salilota australis, Gunther 1887)del Atlántico Sudoccidental

      Perez Comas, J.A. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1980)
      The "bacalao austral" is a typical fish from the cold water of the Southwest Atlantic and the Southeastern Pacific oceans, whose fishery has not yet developed. In this work, the structure of the concentration areas of summer and winter distribution and other biological items were analyzed, basing on data provening from R/V"Walther Herwig" and R/V"Shinkai Maru", which operated in these waters during 1978/79/. The trophic vertical migrations are common in this species.
    • Abundancia relativa y rendimiento máximo sostenible de la merluza común (Merluccius hubbsi)

      Otero, H.O. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1980)
      The statistics provided by the Argentinean Fishing Vessel and the biological data collected by scientist in the last eleven years, allow us to estimate different aspects of the population dynamics of the common hake (Merluccius hubbsi). This work deals with the relative abundance and the maximal sustainable yield of this species, considering the bonaerense stock of the Southewest Atlantic. Analyzing the effective fishing density, concluding remarks can be made. The high catches of 1967 (more than 600.000 tons.)made by the Russian Fleet, affected the fishing density in 1968. Since 1969, the resource recovered the high density level as a consequence of a decrease in the catches and in the fishing effort, but vulnerability of the stock is shown.
    • Observaciones sobre diferencias morfólogicas entre la merluza común (Merluccius hubbsi)y la merluza austral (Merluccius polylepis)

      Cotrina, C.P.; Cousseau, M.B. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1980)
      The species of the Genus Merluccius present in argentine waters, Merluccius hubbsi and M.polylepis are similar externally and it is very difficult to separate them in the capture. Knowing the importance of both species from the commercial point of view, and the need of a correct identification, some morphological characteristics have been compared, looking for external differences, useful for the identification on board. The samples have been taken from the total area of distribution of both species in argentine waters. A total of 154 specimen of Merluccius hubbsi and 105 of M.polylepis were analyzed.
    • Algunos aspectos de la biología pesquera del langostino (Pleoticus muelleri)de la Bahía Blanca y un análisis del desembarco comercial del período 1955-1979

      Bertuche, D.A.; Wyngaard, J.G. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1982)
      This study was carried out in order to get somme knowledge on the characteristics of the fisheries of the shrimp Pleoticus muelleri in the area of Bahia Blanca during 1980-1981. Monthly samplings in the fishing area were performed, and the landing data from 1955 to 1979 were analized.
    • Consideraciones sobre el crecimiento de la caballa (Scomber japonicus marplatensis)durante su primer año de vida

      Sánchez, R.P. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1982)
      Through the analysis of the morphological changes ocurring in the process of growth, it was possible to identify three stages (primary juvenile: 25-75 mm; secondary juvenile: 76-160 mm; and juvenile preadult: 161-250 mm)during the first year of the species life. Regression equations for the different relations studied: body weight/body lenght, body surface/body lenght, body surface/body weight, and metabolic rate/body lenght, have been calculated for each stage. The variation of the number of gill rakers, mean distance between adjacent rakers and mean values of gill rakers lenght in reference to body growth was studied, and the relation between filtering area and body length was established.
    • Distribución y estructura poblacional de la polaca (Micromesistius australis)

      Perrotta, R.G. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1982)
      The polaca (Micromesistius australis)is a typical fish from the cold Malvinas current (temperatures between 3° and 10°C). The species is found in depths between 90 and 800 m and in latitudes from 37°40' to 50° S during winter and spring and from 42°S to 55°S during summer time, over the patagonian shelf and Burdwood Bank. One part of the stock reaches the southern region of the Scotia Sea, the western South Georgias and eastern South Shetland Islands. The dominant food species are Euphausia spp. The polaca is mainly a carcinophagous fish and may be found in a 3-4 trophic level, being one of the main food sources for primary and secondary ichthyophagous fishes.
    • Observaciones sobre embriones de larvas y juveniles de la pescadilla (Cynoscion striatus)

      de Ciechomski, J.D.; Cassia, M.C. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1982)
      Observations on the embrionic and larval development of Cynoscion striatus are presented. The description are made on the basis of material obtained by artificial fertilization. Eggs are pelagic, spherical, 700-840µ in diameter and with single oil globule of 210µ-240µ. The yolk is homogeneous and the chorion has smooth surface. The embryonic development is short and at temperatures of 19°-20°C hatching takes place, 34-36 hours after the fertilization. The larvae at hatching are small, about 2 mm in length and not advanced in their development. The mouth is not functional and the anus is not open. The oil globule is situated in the posterior part of the yolk sac; the position of the anus is close to the posterior end of the yolk sac and the digestice tract forms a straight angle with the anus. The dody and the oil globule are pigmented. The juveniles have a rather deep form of the head and of the body and have their charasteristic pigmentation pattern. The preoperculum is provided with strong spines which disappear entirely in larger specimens.
    • Estudio de edad y crecimiento de la sardina fueguina (Sprattus fuegensis)de las costas de la provincia de Santa Cruz e Islas Malvinas

      Cousseau, M.B.; Gru, D.L. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1982)
      Samples of Sardina fueguina (Sprattus fuegensis)were taken during research cruises carried out in 1974 and 1978. Length and age frequency distributions were analyzed, and von Bertalanffy growth parameters were calculated for the coastal waters of two geographical regions: Province of Santa Cruz and northern part of Malvinas Islands. Lenght and weight growth curves have been calculated for each region and each year. Marked differences have been found between gowth parameters of both regions, and the calculated values showed a good fit with the observed ones. According to these results, it is possible to assume that the sardines of both regions constitute two different populations. However, more information on the total distribution of the species will have to be obtained in order to confirm the present observations.
    • Revisión taxonómica y análisis de los caracteres morfométricos y merísticos de la sardina fueguina (Sprattus fuegensis)Jenyns, 1842 (Pisces, Clupeidae)

      Cousseau, M.B. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1982)
      This paper is based on the study of 484 specimens collected off three different districts of Santa Cruz (Caleta Olivia, Puerto Deseado and Río Gallegos)and the northern coastal region of Malvinas Islands. The following items have been developed: -a brief description of the clupeoids present in the southern patagonic area where the sardine lives, and a key to their identification; -the updated systematic position of the species and its bibliographical references; -a description of the external morphology; -a statistical analysis of morphometric and meristic character; and geographic distribution and movements. It is possible to presume the existence of two geographically separated groups, one in the coasts off Santa Cruz Province and another around Malvinas Islands.
    • Variaciones en el número de miocélulas de la musculatura blanca de la merluza (Merlucciidae, Merluccius hubbsi), en la plataforma argentina

      Christiansen, H.E. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1982)
      This paper describes a method to discriminate different stocks of the Argentine hake (Merluccius hubbsi)based on the counting of white skeletal fibres of the trunk. A total of 713 females were examined from samples coming from a wide area of the Argentine shelf (between 34°30' and 54°00'S)which corresponds to the following systems: Uruguayan, Buenos Aires, northern, central and southern-patagonian. All results may be considered as preliminary due to the incipient nature of the information available on fibre regulation in fish.
    • Aspectos biológico-pesqueros de la merluza de cola del Atlántico Sudoccidental

      Bezzi, S.I. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1984)
      The distribution areas and population structure of the long-tailed hake are analized. Data come from fisheries research cruises carried out by RV Walther Herwig and Shinkai Maru in the Argentine Sea in 1978/79. Macruronus magellanicus is a typical cold waters species of the Southwest Atlantic and Southeast Pacific Oceans. Maximum concentrations were found in the southern Patagonian shelf, in coastal waters and in depths below 200 m. Spawning individuals were observed on the continental slope in the southern extreme of the Patagonian shelf (54°). The distribution area extend to 93,439 n mi² in spring and to 12,368 n mi² in summer.
    • Pigmentos carotenoides del camarón Artemesia longinaris Bate (Crustacea, Decapoda, Penaeidae)

      Carreto, J.I.; Carignan, M.O. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1984)
      Caronetoids from caparace and internal organs of Artemesia longinaris were isolated and identified. The following carotenoid pigments were found in caparace: luteine, tunaxanthin diester, astaxanthin monoester and free astaxanthin. A much greater variety of pigments was isolated from internal organs: Ó- doradexanthin, a fucoxanthin derivate, chlorophylls degradation products and various xanthophylls in trace amounts. These pigments are of dietary origin. In the natural environment, A.longinaris takes preformed astaxanthin from the diet and transfers it to body tissues.
    • Determinación experimental del límite de detección, en el análisis de metales pesados en organismos marinos, por espectrofotometría de absorción atómica

      Moreno, V.J.; Pérez, A. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1984)
      The determination limit is defined as the minimum concentration of a substance in a sample that can be distinguished from the background with a given probability, using a particular analytical method. It is assumed that the concept of detention can be used satisfactorily to quality an analytical method. Some criteria which are necessary for intercalibration purpose are given in this paper. An algebraic method to calculate the detection limit easily and with minimum experimental work was developed. A method to determine the number of repetitions needed when the levels of the analyzed substance are near or under the detection limit of the method is also shown.