Length-Weight Relationship and Condition Factor of Tilapia, Clarias gariepinus, Heterobranchus bidorsalis and Heterotis niloticus in Rivers Niger and Benue, Kogi State, Nigeria

Length-weight relationship and condition factor of Tilapia, Clarias gariepinus, Heterobranchus bidorsalis and Heterotis niloticus from Rivers Niger ( Kabawa) and  Benue (Ogegele) in Kogi State, Nigeria was studied. A total of 288 fish samples were collected from the fishermen catches using gill nets and  fishing basket between July 2009 and December 2010. Length-weight relationship was calculated using the formula W = aL^b which was transformed to base 10 logarithm. Fish sampled had total length ranging from 3.2 and 40.2cm, 25.2 and 44.5cm, 15 to 44cm, and 7.4 to 46cm and weight between 14.8 to 116.3g, 177.6 to 805g, 36.2 to 580g, and 108.3 to 244.5g for Tilapia zilla, Clarias gariepinus, Heterobranchus bidorsalis and Heterotis niloticus respectively. Result showed that regression coefficient (b-value) of 0.4, 3.67, 2.5, and 0.54 and condition factor of 0.2, 8.77, 2.22, and 0.07 for Tilapia, Clarias gariepinus, Heterobranchus bidorsalis and Heterotis niloticus respectively at (P>0.05). Clarias gariepinus with positive value were in better condition because of its average degree of correlation between length and weight in the sampled population. The Kabawa and Ogegele area of Rivers Niger and Benue in Kogi State is a good environment for growth, reproduction and survival of the fish species.