Estudios sobre reproducción y fecundidad de la polaca (Micromesistius australis Norma 1937)en el Mar Argentino

Abstract

An analysis is presented of reproduction aspects of Argentine Sea blue whiting. The species spawns in the study area mostly during August and September, although some spawners have been detected even in November. Total length at 50-per-cent maturity was 35,4 cm for the males and 38.0 for the females. Significant differences between the length of maturity for individuals of the continental shelf compared to those of the slope, have been obtained. The southern blue whiting is a discontinuous spawner, showing one annual reproduction peak. Fecundity was investigated on the basis of samples collected in 1978 by the RV"Walther Herwig" and "Shinkai Maru". A significant positive correlation was also observed at relating oocyte dry weight and gonad factor, whereas no correlation wasobserved between oocyte dry weight and condition factor, and age of the female.