Study on RLG and GaSI of Atherina boyeri in Bishekola-Babolsar region,Caspian Sea

From autumn  2007 to summer 2008 gut content and some food indices such as relative gut length, fullness  index and food occurance were analysed in 342 specimens of Atherina boyeri with local name of Shishemahi in Mazandaran province (Bitween Bishekolah to Babolsar) summer specimens were caught with small mesh beach seine and other Specimens were caught through seasonal sampling as a by catch in beach seen (Parreh).The average size of the fish caught was 99.68±11.23and the average weight was 5.77±2.13Mean value for relative length gut were calculated .46±.10 Relative length gut mean value in summer was 0.32and had high significant difference with this value in other season (P> 0.05). Between females and specimens with non-identical sex, this index show also significant difference (p<0.05).  Mean value for fullness index was calculated 4.1±1.56.fullness index values between seasons were significantly different (P>0.05), but this index did not show any significant difference between different sexes (P≥0.05)