A probable cause of recruitment failure of the Brazilian sardine Sardinella aurita population during the 1974/75 spawning season

Abstract

Eggs and larvae of the Brazilian sardine Sardinella aurita collected during 12 surveys between 1974 and 1993 in the south-east Brazilian Bight, together with temperature data, were used to investigate probable causes of the recruitment failure of the 1975 year-class. During the spawning season, an important oceanographic characteristic of the Bight is the onshore intrusion of nutrient-rich South Atlantic Central Water (SACW). This feature favours larval survival by acting as a retention mechanism for both the prey and spawning products of sardine. The recruitment failure during the 1974/75 spawning season is attributed to the lack of penetration of the SACW, which resulted in high mortality of larvae during that period.