Validation of daily growth of African catfish Clarias gariepinus (Burchell 1822) young-of-the-year from Lake Baringo, Kenya.

The African catfish (Clarias gariepinus) is widely distributed in Africa, where it is a major food fish. The species comprises a significant component of commercial fishery landings in Kenya, and elsewhere in Africa. Nevertheless, little information or data exist on its age and growth characteristics, which is necessary for its sustainable management. This study determined this information from the microstructure of lapillar otoliths of the young-of-the-year (YOY) of the species. Analysis of the otolith microstructure from fish of known age confirmed that one growth increment (circulus) was formed per day, forming the basis for their use to accurately age C. gariepinus YOY collected from Lake Baringo during the months of August and September 2007. The derived length‐age relationship correlated significantly (Pearson Correlation, df = 53, P < 0.05), indicating that the YOY exhibited an average growth rate of 0.2285 cm day )1 . The largest specimen attained a total length of 40.5 cm in only 169 days. These results indicate that native C. gariepinus exhibits rapid growth, achieving a large size during the first year. Thus, they can be recommended for purposes of aquaculture.