Aspect of Reproductive Biology of Fish of Commercial Importance in Sabke Reservoir, Katsina State

Abstract

Aspects of the reproductive biology of the most economically important fish species in Sabke reservoir was investigated such as Fecundity for females, average egg diameter, Gonado Somatic Index (GSI), for a period of twelve month (from March 2009 to February 2010).Samples of fish were collected through both experimental gears and commercial catches from local fishermen fortnightly. Fecundity range of 222 – 9642, and mean of 14652 ± 2600, 197 – 4414, 1110 ± 1162, 77 – 2007, 712 ± 541, 183 – 3290, 1178 ± 901, 265 – 2467, 854 ± 677 was calculated for Clarias gariepinus, Lates niloticus, Tilapia zilli, Oreochromis niloticus and S. galilaeus respectively. Mean annual GSI and average egg diameter of C. gariepinus, L. niloticus, T. zilli, O. niloticus and S. galilaeus of 0.85mm, and 0.60mm, 0.63, and 0.84mm, 1.36 and 1.68mm, 1.83,and 2.02mm, 2.26, and 2.82mm respectively. In general Sabke reservoir indicates positive indices for high fisheries potential.

Key words: Fecundity, egg diameter, Gonado Somatic Index