Growth, Recruitment and Reproduction of Sardines (Stolothrissa tanganicae and Limnothrissa miodon) in Northwestern Lake Tanganyika.

Abstract

Life histories of two cJupeid fish species (Stolothrissa tanganicae and Limnothrissa miodon) in northwestern Lake Tanganyika were studied. S. tanganicae spawns offshore all the year round but more actively in the first half of the year. This fish comes to be exploited by the Zairian artisanal lift net fishery at an age of about 2 months and length of about 3 cm in standard length, and attains 9.35 cm when one year old which approximates to its longevity. L. miodon enters into the exploited phase at an age of 2-3 months and length of about 3 cm, grows up to 9.24 cm when one year, and approaches to an asymptotic length of 13.5 cm. The two species grow to their maximum sizes slowly for their short longevity. They have lower proportions of gonadal weight to body weight than many other fish species, suggesting that they possess a lower level of reproductive effort. An increase in the mesh size of the commercial fishing net is effective in enlarging the exploitable fish biomass.