Browsing by Author "Sabatini, M."

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    Características ambientales, reproducción y alimentación de la merluza (Merluccius hubbsi)y la anchoíta (Engraulis anchoita) en su hábitat reproductivo patagónico. Síntesis y perspectivas
    (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 2004) Sabatini, M.
    Fish recruitment seems to be influenced by environmental variability; the plankton would act as a link between both processes. While environmental variability can be explained in terms of physical forcing, recruitment variability is partly determined by the survival of early larvae. In this review, the available information on hydrography and plankton in relation to reproduction and feeding of hake (Merluccius hubbsi) and anchovy (Engraulis anchoita)in the Patagonian Argentine Sea, SW Atlantic spawning ground was summarized and integrated. The objective was to assess what is actually known about the environmental and planktonic features of the region that may have an effect on the recruitment of both species. In the Patagonian spawning ground, detection, in summer, of two major frontal systems of different nature, with a high planktonic production that would coincide with the spawning and nursery areas of hake and anchovy must be mentioned. Hence, it is suggested to test for the local species some well-known hypotheses about the possible physically-mediated mechanisms that may have an impact on the growth and survival of larvae and juveniles
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    El ecosistema de la plataforma patagónica austral, marzo-abril 2000. Composición, abundancia y distribución del zooplancton.
    (Mar del Plata : Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 2008) Sabatini, M.
    The abundance, distribution and structure of the zooplankton community in southern Patagonia (SW Atlantic Ocean) were studied during late summer (March-April 2000) from samples obtained with Nackthai (390 ~km) and Multinet (150 ~km) samplers. Total concentrations of zooplankton biomass, integrated in the water column, ranged between 1.0 and 14.5 g m-2 (dry weight) and reached the highest values in the mid and outer shelf off Bahía Grande (Santa Cruz Prov., Argentina) (51~'S). The < 5 mm size fraction, composed mainly of copepods represented, on average, 45% of the total; amphipods and euphausiids accounted for 20% and 31%, respectively. Amphipods were, almost exclusively, Themisto gaudichaudii and euphausiids most abundant species Euphausia lucens and Thysanoessa gregaria. Drepanopus forcipatus, Calanus australis and Oithona spp. constituted the dominant copepods with high abundance of the first in the whole area that represented, on average, 85% of the total mesozooplankton. The maximum abundances of Drepanopus forcipatus, recorded in outer waters of Bahía Grande, showed a noticeable decrease towards the inner area and to the north of the bay. C. australis and Oithona spp. concentrations, although much lower, distributed more homogeneously within the whole study area. The distribution of the different populations in the water column varied according to the species: D. forcipatus and Oithona spp. concentrated mainly in the upper layers down to ca. 50 m; C. australis was found between that depth and near the bottom. Copepods populations were dominated by late copepodids.
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    Zooplankton biomass in the reproductive area of the southern blue whiting (Micromesistius australis).
    (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero, 1999) Sabatini, M.; Álvarez Colombo, Gustavo; Ramirez, F.C.
    Total and size-fractioned zooplankton biomass (larger and smaller than 5 mm) were analyzed over two cruises conducted in the late austral winter (September 1994 and 1995) in the area surrounding Malvinas Islands at the time that massive spawning of southern blue whiting was expected to take place. Biomass was rather uniformly distributed in the area and dominated by the fraction larger than 5 mm in which euphausiids and secondarily chaetognaths were dominating in terms of both weight and number. The smaller fraction was mostly made up of copepods. From the high occurrence of euphausiids and seasonal abundance of the several species of copepods normally present within the area it was hypothesised that the feeding requirements of juvenile and adult blue whiting as well as those of larvae and postlarvae may be met during the winter spawning season. The data were also examined in conjunction with the general pattern of zooplankton biomass occurring in autumn and spring in the Southern Patagonian shelf.