The study of growth, population dynamic and larval recruitment of Bivalve, Mytilaster lineatus, in three coastal regions (Amirabad, Khazarabad and Noor) in southern shores of Caspian sea

Growth and recruitment of exotic bivalve, Mytilaster lineatus, was studied in Amirabad, Khazarabad and Noor coasts of the Caspian Sea. This species formation Microecosystems on rocky and stony bases. Samples were collected monthly from May 2003 to May 2004 by quadrate sampling method (43cm2). shell length of 6248 individuals as well as dry weigth and ash-free dry weigth of 1888 individuals were measured in this study. A dominant cohort (CA) in all three sampling stations and cohorts B and A+B in Noor and Khazarabad were observed. The mean length of cohort A of Noor station was lower and population density was greater than the other two (p<0.05). Larval recruitment were observed in Noor (=1.5mm) in August and Khazarabad (=3mm) in September, but no recruitment in Amirabad was obsorved; this indicated the reproduction season during summer. Shell length of M. lineatus strongly correlated with ash free dry weight (R2=0.93, n=388) and dry weigth (R2=0.94, n=388). In addition, we calculated two equations for correlation of shell length with ash free dry weight (W= 0.0717L2.6591, Re=16.3) and shell length with dry weight (W=0.139L2.6924, Re=10) that could be applied in future studies to estimate weight of M. lineatus based on shell length.