Certain reproductive characteristics of the catfish (Clarias gariepinus Burchell, 1822) living in the River Asi, Turkey

Abstract

A total of 523 C. gariepinus caught in the River Asi were surveyed from October, 1996 to September, 1998 to find out the age distribution throughout the population that varied between 0+ and 5 years of age, with the one year age group observed to be dominant in number. Findings also showed that both sexes started to reach maturity at the age of 1, and all the fishes examined had become mature by the end of the second year. The average diameter of ripened eggs was 1.41 - 1.66 mm. They spawned in a period from May to August when the water temperature ranged between 21°C and 30°C. The fecundity observed was related more linearly than exponentially to fish weight, and was formulated by the equation: F = 84.391 W - 31454. Fecundity varied from 4,483 to 336,157 eggs per female.

A total of 523 C. gariepinus caught in the River Asi were surveyed from October, 1996 to September, 1998 to find out the age distribution throughout the population that varied between 0+ and 5 years of age, with the one year age group observed to be dominant in number. Findings also showed that both sexes started to reach maturity at the age of 1, and all the fishes examined had become mature by the end of the second year. The average diameter of ripened eggs was 1.41 - 1.66 mm. They spawned in a period from May to August when the water temperature ranged between 21°C and 30°C. The fecundity observed was related more linearly than exponentially to fish weight, and was formulated by the equation: F = 84.391 W - 31454. Fecundity varied from 4,483 to 336,157 eggs per female.