بررسي برخي خصوصيات زيستي و زيست محيطي صدف دوكفه اي دسته چاقويي Solen dactylus -Cosel,1989 در سواحل بندرعباس

Study of biological characteristics of jack knife clam Solen dactylus (Coscl, 1989) in Bandar Abbas coast

In this study, 945 Specimens of bivalve Solen dactylus were biometrically assessed from April 2007 to March 2008 in two transects of Golshahr coast in Bandar Abbas, Persian Gulf. Physical and chemical factors of water like temperature, pH, salinity, dissolved oxygen, coastʹs sediment, diversity and abundance of phytoplankton were studied monthly during the clam sampling. The mean clam length and total weight were 67.5±17.13mm and 6.3±4.04g, respectively. The relationship between clam length-width, total weight-dry weight and clam length-dry weight were significant (r2 = 0.91, r2 = 0.83 and r2= 0.86, P<0.05). The mean allometric coefficient (b) for relationship between clam length and dry weight was 2.8±0.12 and showed a negative allometric growth style (t-test, P<0.05). No significant relationship between different dimensions of clam with diameter and depth of the canals where clams lived was found (P>0.05). The maximum value of Gonado Somatic Index (GSI) in the first and second transect were 11% and 16%, respectively in January (reproductive cycle). The minimum value of GSI in both transects was zero from April to September. Gonado Condition Index (GCI) was synchronous with the GSI during the year of study. GSI and GCI showed a negative relationship with temperature and a positive relationship with dissolved oxygen.