Distribution of juvenile and adult penaeid prawns Macropetasma africanus (Balss) in Algoa Bay

Abstract

In Algoa Bay, one offshore and four surf-zone sites were sampled over two years, as well as an estuary mouth during two 24-hour studies. Juvenile Macropetasma africanus (< 33 mm in total length) were present in the surf zone throughout the year, major recruitment to that zone taking place in spring and summer at a prawn length of 16–18 mm. Juveniles utilized the surf zone as a nursery area, making up 70–94 per cent of the surf-zone population in summer but less than 15 per cent of the offshore population over the whole study period. Adult males and non-breeding females (> 33 mm) were found in the surf zone throughout the year but moved offshore in August/September. Breeding females were not an important component of the surf-zone population. Adult males as well as non-breeding and breeding females were present offshore throughout the year, the highest frequency of breeding females being recorded in summer. Estuaries are not utilized during any stage of the life cycle.