عنوان مقاله [English]
نویسندگان [English]چکیده [English]
The catch of the sturgeon has declined severely in the last two decades in the Iranian waters of the Caspian Sea. One of the methods for restocking and rehabilitation of the sturgeon stock, is releasing fingerlings and juveniles fish into the rivers leading to the Caspian Sea. In the present study, in order to a quantitative and qualitative evaluation of the sturgeon fingerlings released into the Sefidrood River, which included: stellate sturgeon (Acipenser stellatus), Persian sturgeon (Acipenser persicus) and Ship sturgeon (Acipenser nudiventris), growth indices, weight frequency percentage, growth rate, condition factor, average daily growth and survival percentage of released juveniles were studied during 2017-2018. The total of 1865506 fingerlings of sturgeon released in 2017 from Shahid Dr.Beheshti Sturgeon Restoration and Genetic Conservation Center which comprised Persian sturgeon with 69.3% and the average weight of 2.3±1.01 g, stellate sturgeon with 23.4% and the average weight of 2.34±1.06 g, and Ship sturgeon with 7.3% and the average weight of 5.61±2.56 g, and the total of 1609448 sturgeon fingerlings released in 2018 which included Persian sturgeon with 68% and the average weight of 1.65±0.75 g, stellate sturgeon with 25.5% and the average weight of 2.68±1.4 g, and Ship sturgeon with 6.5% and the average weight was 11.6±4.34g. Based on the Pearson correlation analysis, there were a negative correlation between the number of culture days for two species of Persian sturgeon and stellate sturgeon released during the years 2017-2018 in Sefidroud River and growth coefficient, condition factor, specific growth rate and daily growth rate at the end of rearing period (p<0.05). Also, the mean daily growth rate and specific growth rate of Persian sturgeon and stellate sturgeon fingerlings in 2017 were significantly higher (p<0.05) compared to 2018 and even in stellate sturgeon were higher than in Persian sturgeon.