Resultados de una campaña de investigación sobre la anchoíta (Engraulis anchoita)del sector bonaerense en el otoño de 1983. Distribución, abundancia y algunos aspectos biológico-pesqueros
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An extensive area of the continental shelf -between 37°20' and 34°40'S - was reviewed through hidroacoustical methods in order to evaluate the anchovy biomass. Within the area of highest concentration, further data on anchovy abundance were recorded, and fish samples were taken. Large anchovy shoals were located at about 170 nm from Mar del Plata, mainly in zones with sharp changes in oceanographic conditions. The distribution of the species was not uniform, but "contagious", and the log-normal distribution provided the best fit for the echo-integrator recorded data. The biomass was estimated at 1,061,727 tons (Confidence limits in between 921,010 and 1,223,930 tons). Some parameters of the population were estimated, such as: lenght-weight relationship, von Bertalanffy growth curve constants, sex ratio, maturity, and age composition. Taking into account a calculated naturaly mortality rate of M= 0.85, a Maximum Sustainable Yield at about 451,000 tons was estimated (Confidence limits at about 520,000 and 390,000 tons).