Temporal Variation in Rocky Intertidal Gastropods of the Qeshm Island in the Persian Gulf

Gastropod assemblages were investigated along intertidal rocky shore in the Qeshm Island in the northern Persian Gulf. Monthly sampling was undertaken from May 2007 to April 2008. Environmental factors were also measured in each site. A total of 28 gastropod taxa belonging to 15 families were identified and Cerithiidae was the most abundant family and Cerithium caeruleum was the most abundant species (34.77%). Muricidae with 5 species were the most diverse group followed by Cerithiidae and Cypraeidae each with 4 species. Kruskal-Wallis test yielded no significant differences in gastropod assemblages among months and also different seasons (P>0.05). The analysis of SIMPER showed that spring and autumn had the most dissimilarity among seasons and Clypeomorus bifasciatus was the species of gastropods contributing most to the dissimilarities among seasons (37.54%). December showed the highest value of Shanon-Wiener (2.15) and Simpson (0.85) indices. Lack of significant temporal variation in gastropod assemblages during sampling months suggested that intensity of sampling in future studies could be reduced to seasonal intervals in similar environmental conditions.Where intertidal surveys are restricted by time,and resources such as, personnel and finance.