The Frequency, Age and Growth Bigeye kilka (Clupeonella grimmi Kessler. 1877) in Iranian region of The Caspian Sea (2006-2008)

This research was conducted in commercial fishing areas located at three fishing ports of Babolsar, Amir Abad (Mazandaran) and Anzali (Guilan). Frequency of species, age structure, length and weight ratio, growth parameters of bigeye Kilka were analyzed in the years 2006- 2008. The frequency of this species decreased from 4.7% in 2006 to 2.5% and 1.7% in the years 2007 and 2008 respectively. The mean fork length was 119.2 ± 8.8 mm, minimum and maximum was 77.5 and 147.5 mm (n=865) and 92.5% of the lenght frequency belonged to the groups 107.5-132.5 mm. During the period from 2006 to 2008, the frequency of young fish under 2 years was gradually diminished and the larger fish were observed in commercial fishing, In other words, the population of young fish is severely damaged. Growth parameters of were calculated: L∞ = 148 mm, k= 0.346 , t0 = -1.123 and exploitation rate was 0.58. Annual growth (Ø) was calculated for bigeye of 3.688 which indicates that the growth of this species is faster than the other two Kilka species.