Length-Weight relationships of mangrove oyster, Crassostrea gasar (Adanson, 1757) cultured under continuous and periodic submergence in tidal ponds

Abstract

The length-weight relationships (LWRs) of mangrove oyster, Crassostrea gasar, cultured under continuous and periodic submergence in tidal ponds, for a period of seven months, February to August 2010 were determined. A total of 375 individuals each of pond A (continuous submergence) and B (periodic submergence) respectively were used to derive the length weight relationship parameters. The mean length 42.85±13.55 mm and mean weight 13.76±8.78 g were obtained for the continuously submerged oysters. While for the periodically submerged oysters, mean length 42.59±13.85 mm and mean weight 11.85±7.72g were obtained. The values of regression parameter b were 0.559 and 0.495 for the continuously and periodically submerged oysters respectively. The coefficients of determination (r2) values were 0.743 for the continuously submerged and 0.786 for the periodically submerged. The length-weight relationships (LWRs) were found to be statistically significant (p < 0.001) under both culture conditions.

Keywords: Crassostrea gasar, length-weight relationships, continuous and periodic submergence, tidal ponds, Nigeria