Investigation of some Life history traits of Alburnoides eichwaldii (De Filippii, 1863) in Googgol river_Gorganroad basin

This study was conducted to investigate some biological parameters of Spirlin (A.eichwaldii) from Googgol Stream (Gorganroad basin) from March to September 2015. Sample size was 191 Specimens. The largest specimen of males had 9.3 cm total length and 10.115 g weight, and of females 10.2 cm total length and 15.751 g weight. The mean length and weight (±SD) were 6.22±1.25 cm and 3.38±2.63 g respectively. There was no significant difference between males and females’ abundance, so the sex ratio could be considered as 1:1. The growth pattern was positive allometric (Female: W=0.0093TL3.1527, Male: W=0.0093TL3.1277 , Population: W=0.0087TL3.1781). The studied population included 3 age groups ranging from 2+ to 4+ years. The highest growth rate of males and females was observed between 1+and 2+ages. Based Von Bertalanffy growth function (VBGF) was as Lt=12.28(1-e-0.304(t+0.154 )) for females and as Lt=10.11(1-e-0.251(t+0.512)) for males.