In this study, reproduction biology of the pike (Esox lucius L., 1758) population in IÃ ÂÃÂ±klÃÂ± Dam Lake was examined. A total of 313 individuals were caught from March 2003 to February 2005, monthly, and 196 of them (between 1 and 8 ages) were females and 117 were males (between 1 to 6 ages). Female individuals varied from 21.5 cm (68 g) to 66.0 cm (3342 g), while males varied from 21.0 cm (73.0 g) to 52.3 cm (2363 g). The length differences between female and male was significant (p<0.05), but the weight differences was not significant (p>0.05). The mean condition factors in the age groups varied from 0.798±0.023 (males at age 1) to 1.367 ±0.28 (females at age 6) and the differences between the sex group was not significant (p>0.05). The mean monthly gonadosomatic indices varied from 0.72 ±0.26 (in July) to 20.03±3.88 8 (in February). According to monthly variations of the GSI, spawning of the pike takes place between February (20.03±3.88) and April (3.577 ±0.48). Female pikes reached to the first sexual maturity in the length of 24.9 cm, while males reached to sexual maturity in 22.9 cm. The mean fecundities in the age groups varied from 2517 eggs/fish (first age) and 91944 eggs/fish (at the age of 8). The most relative fecundity was 64291 eggs/kg fish at the second age. The relationship between length and fecundity was expressed as F=1.5844*L2.6669 (r=0.700 ve n=84) and between weight and fecundity was F=124.07*W0.8661 (r=0.743 ve n=84). The eggs diameters varied from 0.691 mm to 2.413 mm ( mean 2.089 mm) and egg size were higher in the older fish.
Meral APAYDIN YACI