Length- weight relationships, condition factor (K) and relative condition factor (Kn) of Sparids, Dentex congoensis (Maul, 1954) and Dentex angolensis (Maul and Poll, 1953), in Nigerian coastal water

Abstract

Length-weight relationship and condition factors were estimated for Dentex congoensis and Dentex angolensis of the family sparidae trawled from Nigeria Coastal water in 2009. A total number of 534 specimens ranging from 7.2 – 3.0 cm in total length and 5.4 – 489.8 g in weight were analyzed. The lengthweight relationship is shown by the following equations: LogW –1.610 + 2.791logL (Dentex congoensis) and LogW = -1.558 + 2.776logL (D angolensis). The two species studied exhibited negative allometric growth (b < 3) with the mean b = 2.78 at p < 0.001. The correlation coefficient (R) values were 0.91 (Dentex congoensis) and 0.98 (D angolensis). The condition factor (K) and relative condition factor (Kn) were determined for each species separately. The condition factor (K) obtained for Dentex congoensis and Dentex angolensis were between 0.86 – 8.04 with mean value of 2.48 ± 0.58 and between 2.06 – 6.13 with mean value of 2.79 ± 0.42 respectively. The relative condition factor (Kn) values were 1.28 ±1.09 (Dentex congoensis) and 1.66 ± 2.44 (Dentex anoglensis). The maximum ‘Kn’ values were recorded during the length at first maturity and there was a general decreased in relative condition factor (Kn) with increase length for the two species.