- ItemPresencia de veneno paralizante de moluscos en higado de caballa de la región costera bonaerense(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero, 1993) Carreto, J.I.; Akselman, Rut; Cucchi Colleoni, A.D.; Carignan, M.O.; Pájaro, M.During november 1992 an intense bloom of the toxic dinoflagellate Alexandrium tamarense accurred in coastal waters from Mar del Plata, Argentina. Toxicity testing of Mytilus edulis populations of the region revealed high levels of paralytic shellfish poison. In order to study the possible PSP accumulation in mackerel (Scomber japonicus), mouse bioassay (AOAC) was performed in livers from individuals captured during December 1992. Liver extracts were lethal to mice; the sumptoms observed were typical of those caused by paralytic shellfish toxins. Although PSPS concentration is below the established limit for human consumption, it suggests that mackerel can accumulate PSP toxins from its food. On the basis of stomach content analysis of sampled mackerel and the related literature, the occurrence of possible toxins vector organisms is discussed.
- ItemCaracterísticas de la red de cerco "tipo lámpara" y algunos comentarios sobre la flota que la utiliza en la pesca de caballa.(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero, 1993) Izzo, A.; Boccanfuso, J.The composition of the fleet is analyzed. The boats range 50-200 HP of engine and have 9-16 m in length overall. Most of the boats have been improving their equipment (echosounders, new engines) since 1980. An inverse relationship was found between sea surface temperature and CPUE as measured by mackerel catch permit time spent on fishing gounds. Yields are negligible over 20°C with a optimum of 20°C.
- ItemSobre la dinámica poblacional de la caballa en la pesquería de Mar del Plata. Período 1980-1990(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero, 1993) Perrotta, R.G.; Pertierra, J.P.This species is a principal basic product of the local canned industry. The results show that the biomass and capture were variable for the studied period as a consequence of change in the capturability, and the fishstock is underexploited. Also was estimated the contribution of recruitment, growth and mortality in the total biomass.
- ItemConsideraciones sobre la alimentación de la caballa con especial enfasis en la depredación de huevos y larvas de peces(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero, 1993) Pájaro, M.Adult and juvenile fish inter and intraspecific predation may be an important source on these first development stages. In this work, adult and juvenile mackerel samples from two areas of Buenos Aires province, one south of Cape San Antonio and the other near Mar del Plata city were analyzed. An important anchovy postlarvae ingestion in both regions considered was observed. A high number of mackerel eggs in the stomach contents from adults was identified. This evidence of cannibalistic behaviour in the argentine mackerel is the first of its kind made in this species and allows to suggest that embryo mortality due to cannibalism might constitute and important percentage of the total embryonic mortality.
- ItemComparación mediante el empleo de los caracteres merísticos y el crecimiento de caballas originarias de varias regiones geográficas (Cataluña, Islas Canarias y Sudamerica)(Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero, 1993) Perrotta, R.G.Mackerel from SW Atlantic (22° -39°S) and the coast of Cataluña (42° 30'N) were compared by analizing both morphometric and meristic characters. A multivariate analysis, i.e. principal components was used. The growth curves corresponding to mackerels from different regions (Canarias, North of Chile, Mar del Plata and Rincón in Argentine) were also compared, as well as the mean length at ages 1 and 2 (Mar del Plata- Cataluña, Rincón- Cataluña). Significant differences in the growth were found between two groups. The first group was integrated by three SW Atlantic population (Brasil, Mar del Plata, Rincón), which possible conform a subspecies of Scomber japonicus. The second one was represented by the coastal mackerel off Cataluña.