Effect of substratum type on Amphibalanus improvisus (L., 1758) settlement in the southern coast of the Caspian Sea

Barnacles are among the most important and abundant sessile animals on hard substrates, particularly in tidal areas. In this study, effect of substratum type on settlement of the barnacle, Amphibalanus improvisus was investigated in Amirabad Port, Southern Caspian Sea, from August 2013 till July 2014. Five substrates (10×10 cm) including PVC, wood, plexiglaas treated with barnacle adult extract, smooth plexiglass and roughed plexiglass were used. Ten replicates per each substratum were horizontally deployed at 1m depth. Substrates were then monthly retrieved and replaced with new panels. Subsequently, number of settled barnacles (abundance), biomass (dry weight), growth (weight per individual) and organic to inorganic material ratio of the barnacles were recorded. Results showed that the number of settled barnacles on PVC panels were significantly higher comparing to the other substrates (p