Population dynamic of the Barbatia decussata (Bivalvia: Arcades) from the Bandar Lenge rocky intertidal shores (Persian Gulf - Hormozgan province)

Document Type : Biodiversity

Authors

1 Department of marine biology, Faculty of biological science, Shahid Beheshti University

2 Islamic Azad University, Tehran Branch, Department of Marine Biology, Marine Biology Department, Iran

Abstract

We studied some aspects of the population dynamics of the ark clam Barbatia decussata in Bostaneh, Lengeh port, Hosseinabbad and Koohen rocky coasts of the Persian Gulf. Samples were collected monthly from August 2011 to September 2012 through quadrate sampling method (area 0/25m2). Shell length of 7064 individuals as well as total live weight and wet weight of 2065 individuals were measured in this study. By length–frequency distribution data, a von Bertalanffy growth function was established with an asymptotic length of 57.75mm, growth constant of 0.47year-1 and t0 (age at zero length) of -0.29 year. Asymptotic weight, natural mortality and longevity were 40.38g, 0.92 year−1 and 6.29 years respectively. We calculated two equations for the shell length with total live weight (TLW= 0.0001SL3.181) and shell length with wet weight (WW=0.000015L3.347) relationships that could be applied in future studies to estimate weight of B. decussata based on shell length. In this study shell length- age also total weight - age relationships were Lt= 57.75 [- e-0.47 (t + 0.29)] and Wt= 40.38[1-e-0.47 (t+0.29)]3 respectively. The growth performance index was 3.2 and the “b” value of the shell length– total weight relationship was 3.181 during the study period. Sex ratios did not significantly deviate from the proportion of 1:1 and the recruitment pattern was continuous with 2 major peaks.

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