Abstract: A study of intertidal gastropods using quadrat method was conducted from August 2012 to July 2013. Specifically to identify and classify taxonomically the gastropods in Asry Beach, Kingdom of Bahrain; find out significant differences in the number of identified gastropods within the taxonomic groups; and determine heterogeneity and alpha diversity of species using Shannon diversity index (H), and species richness using Magalef’s (d) diversity index. A total of 2,136 individual species were identified in the sandy and rocky intertidal zones which belong to 16 families, 5 genera and 28 species of gastropods. Statistical analysis using Analysis of Variance (ANOVA) with multiple comparisons depicted significant difference on the number of gastropods at varying taxonomic groups. Result of Shannon (H) and Magalef’s (d) diversity indices revealed diversity and species richness of the three species, Calliostoma selectum, Lirobittium attenuatum, and Homalopoma luridum. Gastropods are abundant in the sandy and rocky intertidal zone.

Keywords: Gastropods, Intertidal zone, Quadrat method, Magalef’s diversity index.