Length-weight relationship and condition factor of Sphyraena afra from the coastal waters of Lagos State

Abstract

Abstract The length-weight relationship and condition factor of Sphyraena afra from the Lagos coast (LC) and the Lagos lagoon complex (LLC) in the coastal waters of Lagos State were studied for a period of two years. Parameters a and b of the length-weight relationship were estimated using the equation W = a x TLb, while the condition factor was calculated with the equation K = 100 x BW x TL-3. The relationships of fish condition factor and body length, sex, and seasons in Lagos coastal waters were determined. The species exhibited negative allometric growth (b < 3, P < 0.05) for males, females, and combined sexes with the length exponent (b) ranging from 2.72 to 2.85. Correlation coefficient r ranged from 0.89 to 0.98. The allometric growth values obtained in LC and LLC from the length-weight relationship indicated that the fish species exhibited increases in length rather than in weight. The overall mean condition factors (K) for S. afra from the LC and the LLC were 0.97 ± 0.11 and 1.17 ± 0.12, respectively. The mean condition factors of females were higher than those for males at most of the sampling stations, and S. afra was observed to be in better condition during the dry season.