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The establishment of protein and lipid requirements for growth of penaeid species is essential in maximizing productivity but information on the effects of these nutrients on gonad maturation is still lacking. Indian white prawn, Penaeus indicus (H. Milne Edwards) broodstock, were fed formulated maturation diets containing varying levels of dietary protein (35, 45 and 55%) and lipid (6, 12 and 18%) combinations following a 3×3 factorial design. Control group was fed with fresh mussel, squid and polychaete. Results indicate that treatment groups receiving diets of 45/18 and 55/12 protein/lipid combinations and the control exhibited higher maturation rates than the other treatments (p = 1.9 × 10−4). Shrimp broodstocks fed diets containing the lowest protein or lipid levels exhibited poor gonad maturation. Hepatopancreas damage and gonadal atresia were apparent in treatments with high dietary lipid based on histological and biochemical analyses. The diet with 55/12 protein/lipid combination is therefore best recommended for P. indicus gonad maturation. This study demonstrated that a well‐formulated diet that satisfies the protein and lipid requirements can support successful gonadal maturation comparable with feeding the broodstocks fresh maturation diets.

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Based on similarity of natural features of salinity, turbidity, soil substrate, mangrove vegetations and intertidal flat of the stations studied, there were three habitats (A, B, and C) of Scylla serrata (Forskål, 1775) in Lawele Bay. The characteristics of habitat A were preferred by S. serrata since it had the highest relative abundance of S. serrata. With relative abundance of 11.87%, habitat B as transition habitat between habitats A and C was less preferred by S. serrata. The characteristics of habitat C were in contrary with habitat A and S. serrata caught was only 1.19%. The relative abundance of S. serrata at habitat A differed significantly with habitats B and C (p < 0.05), while at habitat B was not significantly different with habitat C (p > 0.05). It suggests that S. serrata tended to move forward at habitat A and occupying such habitat which was characterized by low salinity, high turbidity, the thickest mangrove vegetation, muddy substrate and the widest intertidal flat. The relative abundance of males was significantly different with females either during flood tide or ebb tide (p < 0.05). Both sexes had two peaks of abundance. A major peak was in July and August and a minor peak in February. The lowest relative abundance was in December. However, seasonal relative abundance was not significantly different (p > 0.05). It suggests that the relative abundance may depend on seasons but they are found all year round.

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