Some biological aspects of European seabass Dicentrarchus labrax in Egyptian Mediterranean water and aquaculture, Egypt

Biological aspects between cultivated and wild sea bass, Dicentrarchus labrax were evaluated. Fish samples were collected seasonally from Boughaz El-Maadiya in the eastern Mediterranean coast and fish farm. The length-weight relationship of seabass from two habitats were calculated and condition factor for seabass captured from El-Maadiya region (Mean ± S.d = 1.044 ± 0.0905) was lower than that for fish farm (Mean ± S.d = 1.158 ± 0.8119). The mean value of natural mortality coefficient for wild seabass was 0.172 ± 0.017. Significant seasonal difference in degrees of stomach fullness of seabass from El-Maadiya region (F = 3.589, df = 3, p<0.05) and fish farm (F = 8.381, df = 3, p<0.01). sex ratio for seabass from El-Maadiya region (X2 =5.21, p < 0.05) differ significantly from cultivated in fish farm. The average of gonadosomatic index (GSI) (0.258 ± 0.2865), hepatosomatic Index (HSI) (1.20 ± 0.5714) and spleen-somatic index (SSI) (0.102 ± 0.0518) for fishes from El-Maadiya region was lower than GSI (0.940 ± 1.5601), HSI (1.486 ± 0.5247) and SSI (0.157 ± 0.2406) for cultured seabass.