Seasonal distribution and Condition factor of Clarias gariepinus from polluted Oluwa River, Nigeria

Abstract

The Condition factor (k) of the Clarias gariepinus species in Oluwa River, Nigeria was done. Samples were collected monthly over a two-year period from July 2010 to June 2012 and were identified using standard method. They were subjected to morphometric studies including determination weightand lengths. Condition factor was calculated in relation to sex and sizes. The mean condition factor for males exhibited a range of 0.81±0.03 - 1.97±0.33 (mean 1.34±0.10) while those of females exhibited a range of 0.64±0.00 - 2.00±0.21 (mean 1.31±0.09)and that for combined sexes ranged from 0.54±0.27 to 1.94±0.11 (mean 1.31±0.10). In relation to total length range (TLR), males had the highest condition factor at 34.00 - 36.90cm while the least was recorded in 70.00-72.90cm range. Females had the highest condition factor in the range 37.00- 39.90cm and the least at range 70.00-72.90cm. For the combined sexes, highest condition factor was recorded in the TLR 37.00-39.90cm while the least was also recorded in the TLR 70.00-72.90cm. The mean 'k' indicated that male fishes were not in good condition in the months of July, August and November. Generally, male fishes and smaller sized fishes were found to be better suited to the environmental condition than the female and bigger fishes.