Abstract
A total of 107 fishes of crusian carp, Carassius carassius L.,1785 were caught from Tigris-river during March, April and May for determinating of fecundity,sex ratio and age at sexual maturity.It was shown that absolute fecundity ranged between 3360-79402 eggs for total length of 117.3-264mm, while the relative fecundity was ranged between 119.6-316.9 eggs for each gram of body weight for the total weight of 21.8-250.5 gm. the largest egg dimeter was 1.5mm, and the most correlation of fecundity was with gonad weight (o.99). Females were most dominant during the three months and the total sex ratio for the total fishes was 26.04%:73.96%(males: females). Chi-squares showed differences between the sex ratio (x2, p0.05).
