Study on growth properties of Carassius gibelio (Bloch, 1782) in Golestan and Voshmgir dam lake of Golestan Province- Northern Iran

In this study, age and growth parameters of Prussian carp C. gibelio were examined using 247 specimens catched from the Goletan dam lake and 208 specimens from the Voshmgir dam lake. Sampling was carried out monthly over the period of February to September 2015. Total size distribution varied from 41 to 196 mm in length and 1.25 to 141.35 g in weigh and from 44 to 240 mm in length and 1.73 to 280.6 g in weigh in the Golestan and Voshmgir dam lakes respectively. Length-weight relationship of population was calculated as W = 0.021 TL2.92 in Golestan dam lake and W = 0.027 TL2.79 in Voshmgir dam lake. The parameters of von Bertalanffy growth fit the mean observed total lengths-at-age for each sex separately and were estimated as L∞= 378.09 mm, k = 0.12 year -1, t0= -0.43 year for females, L∞= 309.38 mm, k = 0.17 year-1, t0= -0.02 year for males, and as L∞= 355.74 mm, k = 0.13 year -1, t0= -0.35 year for combined sexes in the Golestan dam lake, L∞= 408.70 mm, k = 0.52 year -1, t0= -0.20 year for females, L∞= 186.23 mm, k = 0.51 year-1, t0= -0.42 year for males, and as L∞= 302.94 mm, k = 0.04 year -1, t0= -0.73 year for combined sexes in the Voshmgir dam lake.