• 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.
    • El aceite de pescado argentino y sus posibilidades de utilización en procesos industriales. Parte 1. Variación estacional de sus propiedades y composición en ácidos grasos

      Cuello, O.M.; Carrizo, J.C.R. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1986)
      As a result of preliminary works, it is possible to conclude that the argentine fish oils could be proper raw materials for the preparation of sulfated oils and another industrial products. In this work, the physicochemical properties and the fatty acid composition of twelve samples of fish oils were determined monthly during a year in order to evaluate their seasonal variations and the probable incidence on their potential applications.
    • El aceite de pescado argentino y sus posibilidades de utilización en procesos industriales. Parte II. Obtención de derivados sulfatados para la nutrición de cueros

      Carrizo, J.C.R.; Cuello, O.M. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1986)
      Twelve sulfated oils were prepared from Argentine's raw fish oils, and three more from samples previously bleached. The samples were taken montly during a year at a factory in the Mar del Plata (Argentine)zone. Each oil and its sulfated derivative was analyzed in its physico-chemical properties. The hydrophilic and hydrophobic fractions were separated and the fatty acids composition of the latter were determined. From the results obtained, it is possible to conclude that the Argentine's fish oils sulfated will be able to be used in fat-liquoring of leather.
    • Acerca del poder de pesca y capturabilidad en la pesquería de caballa (Scomber japonicus) de Mar del Plata

      Perrotta, R.G. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1988)
      Analyzed in this paper is the structure of the fleet applied to mackerel fishing based at Mar del Plata Port (38° LS); an attempt is also made at establishing the best system for measuring the fishing effort; the changes in catch capability (availability and vulnerability)are duly analyzed. Sampling vessels that allow greater data, particulary by in relation to the fishing effort, are available since the 1983/84 fishing season.
    • Actividad reproductiva del salmón de mar (Pseudopercis semifasciata) en aguas costeras de la Provincia de Buenos Aires en el período 2012-2014.

      López, S.; Militelli, M.I. (2017)
      The reproductive activity of Argentine sandperch (Pseudopercis semifasciata) in the Buenos Aires Province coastal waters close to the Quequén/Necochea port, Buenos Aires, Argentine sea, was analyzed. The material derived from landing samplings performed by the Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP) in the 2012-2014 period. The study of gonadal maturity stages allowed to determine that the species reproductive time in the area extends from August through February, with a marked increase of the gonadosomatic index and the presence of females in spawning activity or with postovulatory follicles, indicators of recent spawnings. Batch fecundity, that showed a positive relationship with the length and weight of ovary-free females, had a mean value of 93,483 hydrated oocytes. Relative fecundity varied between 18 and 51 oocytes per gram of ovary-free female and showed a negative linear relationship with length and weight. The dry weight and diameter of hydrated oocytes and the oily drop did not relate to the maternal characteristics in a significant way. The largest landings, that took place in March, September and October, showed that the last two months coincided with the time of the highest reproductive activity of the species.
    • Age and growth of Whitemouth croaker (Micropogonias furnieri) larvae and juveniles.

      Braverman, M.; Brown, D.R.; Acha, E.M. (2017)
      With the aim of studying the age and daily growth of whitemouth croaker (Micropogonias furnieri) larvae and juveniles, the microstructure of sagittae otoliths of 122 individuals 3-25 mm standard or notochord length (SL or NL) size range and 7-92 days old was analyzed. Specimens derived from the turbidity front of the Río de la Plata area (Argentina) the main spawning zone of the species. Counting and measuring of the increments width along the otolith major radius were performed. The length-at-age data were fitted to the linear model (R2 = 0.875) and that of Laird-Gompertz (R2 = 0.881) with L0 = 2.44 and 2.76 mm, respectively, that represents the average length at hatch. With the Laird-Gompertz model an inflection point at 31 days and 10.23 mm SL was obtained. The instantaneous growth rates as a function of length showed a bell shape with an increment of 0.19-0.28 mm day-1 (27 mm SL asymptotic length). The growth rate derived from the linear model was 0.25 mm day-1. A linear relationship between the otolith major radius and length was found. The analysis of increments width as a function of age showed a trend similar to the one described in the Laird-Gompertz model.
    • Algunas características de la estructura y del comportamiento migratorio de los cardúmenes de caballa (Scomber japonicus marplatensis)en la plataforma bonaerense (Mar Argentino); período 1965-1984

      Cousseau, M.B.; Angelescu, V.A.; Perrotta, R.G. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1987)
      Three periods were distinguished during the analyzed years: the first one (1965-1975)may be defined as "normal fishing seasons" occurring from October to March, with catches between 8,000 and 14,000 tons.
    • Algunas características del florecimiento del fitoplancton en el frente del Río de la Plata. I. Los sistemas nutritivos

      Negri, R.M.; Carreto, J.I.; Benavides, H.R. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1986)
      During the spring (H-04/82: october 11-27, 1982)carried out by the Fishery Research Vessel "Dr.E.Holmberg", the distribution of temperature, salinity, nutrients concentration and photosynthetic pigments were studied at the "Rio de la Plata" maritime front. The presence of Sub-Tropical coastal waters in only station did not allow its characterization. Low Chlorophyll a concentration were noted, in association with scarce concentrations of nutrients and high Margalef index values.
    • 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.
    • Alimentación de la anchoíta argentina (Engraulis anchoita Hubbs y Marini, 1935)(Pisces: Clupeiformes) durante la época reproductiva.

      Pájaro, M. (Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), Mar del Plata, 2002)
      Northern and southern populations of Engraulis anchoita spawn during spring and early summer in the coastal and intermediate shelf regions of the Argentine Sea between 34°S-41°S and 41°S-48°S respectively. Samples were obtained in 8 research surveys carried out during the spawning peak of the species. In both populations, more than 70. of the stomachs analyzed were empty or with scarce food. In plankton samples taken copepods predominated in the whole reproductive area. However, densities (41,000 individuals m-2)were lower than those found on the external shelf. Distribution and number of preys observed in the stomach content were associated to the distribution and abundance of plankton organisms. When comparing coastal and shelf regions it was noted that 77. of the total copepods ingested by both anchovy populations were depredated in the Patagonian area. Time spent on feeding ranged from 11-13 h, from 3.30-6.00 a.m. to 5.00 p.m., with an unclear peak around 4.00-5.00 p.m. This behaviour would be a consequence of the lower food density available in the reproductive habitat and the time schools spend on reproduction. The results imply that schools of E. anchoita are in a continuous search for food in the reproductive area, that they have short feeding migrations offshore and return to the coastal region to continue spawning.
    • Alimentación de Merluccius hubbsi e impacto del canibalismo en la región comprendida entre 34°50'-47°s del Atlántico Sudoccidental.

      Sánchez, M.F.; Garcia de la Rosa, S.B. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1999)
      Feeding of Argentine hake during winter 1994, between 50 and 370 m of depth, in the studied area (34°50'-47°S), is based on the consumption of zooplanktonic crustaceans, fishes and cephalopods. Maximum feeding incidence is found at 36°-40°S (51. ), in sea layer of 80-130 m deep (62. ) and between 8:00-10:00 hours (36,6. ). Cluster analysis shows five spatial groups, with similar length distributions and characteristic principal prey items combination. The males of all sizes show a trend to feed on euphausids and hiperiids amphipods. The females eat more quantities of hake, short fin squid and other fishes. There is a change in diet related with predator size, from 47 cm TL onwards for males, and from 53 cm TL for females. This change consists in a decrease of macrozooplanktonic crustacean consumption and an increase of fish in diet. There is a decrease in the predation of all preys, with the increase of the depth, except for mictophids fishes, which prevail from 130 m onwards. During the morning hours, all prey items show maximum values in stomach contents. The midday feeding is related with the water layer close to the bottom layer, when hake principally consumes bentic macrocrustacean. Southerly of 44°S the intake of fishes and cephalopods increases. From total hake cannibalized number, 95,7. corresponds to those hakes smaller than 24 cm TL (ages 0 to 2), which were predated by hake group among 35-. 49 cm TL (ages 2 to 7). Cannibals size is between 15 and 81 cm TL (ages 0 to 10)and 47. of them belonged to ages 0 to 2. Cannibalism was greater between 34°-39°S, at depth less than 100 m of depth, where bigger juvenile stocks are concentrated.
    • Alimentación de Squalus acanthias y predación sobre Merluccius hubbsi en el Mar Argentino entre 34°47'-47°S.

      Garcia de la Rosa, S.B.; Sánchez, M.F. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1997)
      The spiny dogfish, Squalus acanthias is an euribatic, euritermic and cosmopolitan specie. In the Argentine Sea it consumes diversity of preys, characteristic of a generalist and oportunist feeder, butits principal food items are ctenophores, fishes and cephalopods.Diet overlap between sexes was found between 34°-37°S and 101-150 m,where males principally feed on fishes, squid and polichaetes,sharing only ctenophores and hake consumption with the females. Near 62 cm TL there is a shift in the diet, due to an increment of argentine hake Merluccius hubbsi and squid Illex argentinus predation and a diminution in ctenophores Pleurobrachia pileus eating. Feeding shows an increment from north to south, its mode on 42°-43°S.Argentine hake is an important prey between 34°-35°S and 100-150 m deep and southern to 42°S, less than 80 m deep. No feeding differences were found during daylight hours for Squalus acanthias is a continuous feeder. This species nearly overlaps it is distribution area with the one of argentine hake. Thereby, interespecific overlapand sharks predation pressure is almost permanent on juvenile andadult Merluccius hubbsi and it is higher southern to 44°S.Predation on 5-34 cm LT argentine hake occurs at 32-88 cm LT predator length, but the highest predation pressure is focalized on those smaller than 25 cm. There is a partial diet overlap between Squalus acanthias and Merluccius hubbsi. This fact does not implie competence, for each species does not overlap principal food items.
    • Alimentación del calamar Illex argentinus en la región patagónica durante el verano de los años 2006, 2007 y 2008

      Ivanovic, M.L. (2010)
      The information gathered during four research cruises carried out in January and February of 2006, 2007 and 2008 allowed to analyze the summer feeding pattern of Illex argentinus squid in the shelf and slope of the Patagonian region (43º S-51º S), SW Atlantic Ocean. Intake, that took place during daytime, had its peak as of midday. Of the preys eaten amphipods and euphausiids, two groups of zooplanktonic organisms, represented 71-99% of the diet. The most frequent preys found in three of the four cruises corresponded to amphipods, represented by a single species, the hyperiid Themisto gaudichaudii, that accounted for over 50% of the food consumed. When depth of the catching area was beyond 100 m an increase in consumption of squid and fish by specimens above 20 cm ML was observed. No clear trends were found between the type of prey consumed and the time of catches or the degree of stomach repletion of the predator. The diet, of low diversity, showed that 56-62% of the squids studied fed on a single type of prey.
    • Análisis de la unidad poblacional de la merluza de cola (Macruronus magellanicus). Estudio de las variaciones morfológicas somáticas y de los otolitos en relación con su distribución geográfica

      Jerez, B.; Hernández, D.R.; Giussi, A.R.; Malaspina, A.M. (2013)
      To determine the existence of different population units of longtail hake (Macruronus magellanicus) of the Argentine Sea, the meristic and morphometric characters of 861 specimens from two different areas were studied measuring 24 body distances with the landmark methods. Besides, the relation among weight, width and thickness of 806 pairs of sagittae otoliths as a function of length and sex of individuals was analyzed. Using the General Linear Model, the Principal Component Analysis and the Multivariate Analysis of Variance the fitted morphometric variables, the meristic characters and their relation to the Area and Sex factors were assessed. The variability observed does not show any conclusive evidence about the existence of more than one stock in the Southwest Atlantic Ocean.
    • Análisis de los desembarques declarados de condrictios a partir de la implementación de la veda en el área del tratado del Río de la Plata y su Frente Marítimo (2006-2014).

      Bernasconi, J.F.; Monsalvo, M.; Prosdocimi, L.; Martínez-Puljak, G.; Navarro, G. (2016)
      In 2007 the Comisión Técnica Mixta del Frente Marítimo established a closed area to bottom trawl in fishing rectangle 3656 to protect chondrichthyan reproductive aggregations and juveniles. The aim of this work was to analyze the evolution of said measure, the skate and shark landings declared during the 2006-2014 period in said rectangle and the distribution of the fleet before and after implementation. In the period evaluated, the duration of the closed area it was extended from 59 to 151 days and a reduction of tonnes of skates and sharks declared in the Argentine Uruguayan Common Fishing Zone of rectangle 3656 and an increase in the participation of said species in landings of the area of provincial jurisdiction was observed. The same trend was proved in the fishing activity if compare the season 2006-2007 (without closed area) and the season 2012-2013 (with closed area). During the closed season a northeast displacement of activities, a high catch level and fishing operations in the adjacent rectangles were observed.
    • Análisis de poblaciones virtuales modificado a partir de una aproximación a la ecuación de captura permitiendo una implementación numérica sencilla.

      Hernández, D.R.; Mendiolar, M. (2017)
      A modification to the Virtual Population Analysis as a result of an approximation to the catch equation that allows to avoid solving nonlinear equations in each cohort reconstruction process is presented. The relative errors obtained when estimating the fishing instantaneous mortality rate per age (maximum and mean in absolute value) remained lower than 1.4 percent within the M and F range values (natural instantaneous mortality rate and fishing instantaneous mortality rate) considered (0 menor o igual que M menor o igual que 1.2 y 0 menor o igual que F menor o igual que 2). The new method can be adapted to a particular situation (M and F range values) by simply solving an optimization problem (minimization of the maximum relative error absolute value) easily achieved using a calculation sheet or considering the approximation corresponding to any of the domains hereby analyzed.
    • Análisis dinámico-teórico de la relación entre la longitud del cable de arrastre y la profundidad de pesca para una rastra destinada a la captura de vieira y desarrollo del software de aplicación.

      Roth, R.R.; García, J.C.; Villalba, J. (2017)
      In this work the length of the trawl cable as a function of fishing depth for Patagonian scallop (Zygochlamys patagonica) catch at Argentine Sea, with dredge is determined in a theoretic way. A calculation sheet was designed to establish the cable length as a function of different parameters and develop an application software to estimate, in a quick way, the length/depth relationship. The software can be run in different devices of the Android or Windows operative systems and be integrated to the "CAPtura" database system used in Patagonian scallop assessment cruises. The calculation sheet allowed to determine that, if the dredge is operated at a trawl speed of 4 knots and 100 m fishing depth, the length/depth ratio should be close to four (4) to guarantee that the gear is in permanent contact with the seabed, especially at the beginning of the operation, when the absence of retained catch reduces the equipment weight. In order to obtain more accurate calculations to allow for a reduction of the security coefficient used to establish length, the tension generated in the cables should be measured in an actual work situation. Due to the lack of data about the coefficients of friction with the different types of seabed, those established for soil tillage were adopted, which meant a source of errors in calculations. In order to improve the estimates obtained, it is necessary to perform studies to determine them. The calculations made lead to conclude that the cable length is directly related, among other factors, to the trawl speed, the depth at which the work is performed and the weight of the fishing gear.
    • Análisis exploratorio basado en caracteres morfológicos y en landmarks en tres especies de granaderos de la familia Macrouridae: Coelorinchus fasciatus, Macrourus holotrachys y Macrourus carinatus.

      Jeréz, B.; Hernández, D. (2015)
      In order to identify Coelorinchus fasciatus, Macrourus holotrachys and M. carinatus, three grenadier species, 349 individuals were analyzed and 16 morphometric variables were explored using landmarks. Each variable was fitted considering the linearized allometry relationship eliminating the size effect. The null hypothesis of equal slopes was tested and the Principal Components Analysis (PCA) performed for each variable and each species. The results obtained allow to conclude that the major differences are found between C. fasciatus and M. carinatus. PCA detected those differences in the morphology of the cephalic region of species of the Coelorinchus and Macrourus genera. In M. holotrachys and M. carinatus, the two large grenadiers species, differences were found in the anterior portion of the head, specifically in the orbital region. The result of the length-weight relationship analysis between pairs of species showed disparities between C. fasciatus and M. carinatus.
    • Análisis secuencial de la población de merluza de cola (Macruronus magellanicus)en el atlantico sudoccidental período 1985-1995.

      Wöhler, O.C.; Giussi, A.R.; Hansen, J.E. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1999)
      Sequential population analysis on Long Tail Hake (Macruronus magellanicus)from the Southwest Atlantic. Years 1985-1995. VPA on the Long Tail Hake (Macruronus magellanicus), based on data covering the years 1985 up to 1995, was performed to assess the current state of the stock. Simulation trials, inducing uncertainty about both the natural mortality rate and recruitment were also accomplished, to evaluate the risk of overfishing which is associated to different fishing alternatives, always under the assumption of a single and closed Long Tail Hake population. CPUE data were not appropriate for tunning, so the traditional VPA has been applied. During the period of study, stock biomass and spawning stock biomass showed an increased trend. Long and short-term predictions about yield, stock biomass and spawning stock biomass were made under variable fishing mortality levels. Management measures have been adviced under the assumption of M = 0.35. The analysis showed that a fishing mortality rate F= 0.15 could be recommended as one exploitation alternative without risk of overfishing. On the other hand, F0.1, and F30. BRV involve a higher biological risk. During the last four years, total Long Tail Hake catches have been quite stable, about 40 thousands tons. The recommended fishing mortality would mean to increase 5.5 times fishing effort in relation to that applied in 1995, which would be equivalent to allow for a total catch about 180 thousand tons during 1996, including either Argentine float and Malvinas licensed vessels. The simulations indicates that if equal efforts were successively applied, yields would begin to be stabilized about 145 thousand tons by the year 2000.
    • Análisis secuencial de la población de polaca (Micromesistius australis) en el período 1987-1997 ajustado con valores de rendimiento por unidad de esfuerzo de pesqueros comerciales.

      Wöhler, O.C.; Cordo, H.D.; Hansen, J.E.; Cassia, M.C. (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 2001)
      The current status of southern blue whiting Micromesistius australis stock is described. A single, closed fish population is assumed to inhabit the SW Atlantic. Based on catch data corresponding to years 1987-1997, a sequential analysis on the stock is carried out (Cohort Analysis). Under an adaptative framework, catch per unit of effort data from commercial vessels are used to fit the model. Two commercial fleets are used in the fitting, i.e. Polish vessels (1987-1994)and Argentine surimi factory vessels (1991-1997). Results indicate that both, total stock biomass and spawning stock biomass would have declined. Total biomass would have decreased from a maximum close to 1.4 million tons in 1990 down to 0.5 mt in 1997 whereas the current spawning stock biomass would be 30 below the virgin spawning stock biomass. Recruitment also showed a decreasing trend to become extremely poor by the last part of the period. That seems to be the main cause of the stock biomass decrease although the exploitation rate is relatively high (0.60)and the current fishing mortality (0.22)above the biological reference points (F(30)=0.20)and much higher than the one considered as management objective (F(0.1)=0.14). Simulation trials were performed to project the future evolution of stock and catches under three different exploitation levels (no fishing; fishing under F(0.1); fishing under F(1997)). Whatever the exploitation level, if recruitment maintained its current status, the stock would suffer a sharp decrease to stabilize at very low abundance levels. In the short term, projections forecast a remarkable decrease of catches for 1998 that, even at the effort level exerted at present, would be over 73 thousand tons. Considering the current status of the stock, a series of measures to be applied in the short term are suggested. Such measures include a 35 reduction of the effort exerted in 1997 to limit fishing mortality to the F(0.1)=0.14 reference point and promotion of parallel actions by Argentina and the United Kingdom to achieve recovery of the resource.