age, growth and some biological characteristics of silver bream (blicca bjoerkna l., 1758) (cyprinidae) from aras dam lake in northwest of iran

we collected silver bream blicca bjoerkna from march to july 2013 from aras dam lake (north-west of iran) and investigated its age, size, and some biological characteristics. the maximum age was 5 + years. the total length and weight of specimens ranged 137-278 mm and 26-247 g for male and 134-282 mm and 26-289 g for female, respectively. length-weight relationship was estimated as w = 1e-06tl 3.44 for females, w = 1e-06tl 3.45 for males and w = 1e-06tl 3.44 for the sexes combined. sex ratio was 1:1.42 in favor of males. the growth model was positive allometric for males, females and sexes combined. the calculated maximum condition factor was 0.34 in male and 0.37 in female. the most frequent age classes in the samples were 2 + years for males and females.