Reproductive biology of the anchovy (Stolephorus commersonnii, Lacepède, 1803) and spotted sardine (Amblygaster sirm, Walbaum, 1792) from Tanga Region, Tanzania

The present study investigated the reproductive biology of Stolephorus commersonnii and Amblygaster sirm at two landing sites in Tanga on northern coast Tanzania. Fish samples were collected a monthly basis from ringnets operated by artisanal fishers nearby coastal waters. Spawning seasons determined using gonadosomatic index (GSI) gonadal maturity stages. size first was 57.7 mm 66.2 total length for male female S. respectively. Male A. estimated to attain 147.7 169.2 spawning both species protracted. demonstrated year round cycle with peaks August, October January. peak season recorded August September Both exhibited skewed size-dependent sex ratios females predominating larger classes. had higher fecundity rate maximum 96,500 eggs largest fish 258 as compared (10,055 eggs) 98 mm. mean (±SE) comersonnii 5,134.7 ± 136.9 eggs, 47,029.03 1,435.13 sizes 68 170