Population dynamic and distribution of Barbatia decussata (Bivalvia: Arcidae) on rocky intertidal shores in the northern Persian Gulf (Iran)

摘要

Barbatia decussata is a member of intertidal communities occurring at rocky shores in the northern Persian Gulf. Population dynamic for this clam was explored from August 2011 to September 2012 on rocky intertidal shores in the northern Persian Gulf. The results showed that the Ark clam mostly occurred in the middle followed by lower intertidal zones and its distribution was associated with substrate morphology mostly occurring on shaded sides of boulders and cobbles followed by in crevices. Total shell length (SL) for 7064 individuals of Ark clams ranged from 2.21 to 53.93mm. The growth parameters for the von Bertalanffy function were L-infinity=57.75mm, K=0.47 year(-1), and t(0)=-0.29 year. The growth performance index (phi '), longevity, asymptotic weight (W-infinity), and natural mortality were 3.2, 6.29 years, 40.38g, and 1.79 year(-1), respectively. The exponent "b" value was 3.181 indicating that this clam bears a positive allometric growth pattern. The recruitment pattern was continuous with two major peaks. The sex ratio did not deviate from 1:1. The SL-total live weight (TLW) relationship, the SL-wet weight (WW) relationship, the SL-dry weight (DW) relationship, and the SL-ash-free dry weight (AFDW) relationship were TLW=0.0001xSL(3.181), WW=0.000015SL(3.347), DW=0.000009SL(3.047), and AFDW=0.000009SL(3.22), respectively.