Study on the intertidal zones along the cobble bed in Bushehr province (Persian Gulf), based on the macrobenthic distribution pattern

Similarity of the pattern distribution of macrofauna in the intertidal zone was studied at two cobble stations in Bushehr province, during winter and summer 2014, and spring 2015. In this study, 1495 individuals (N/m2) were collected. These are classified by similar biological, nutritional or reproductive characteristics into 12 groups and are arranged in the following taxa-groups dominancy: [Mollusks > Peracarid > Balanus > Xanthoid crabs > Echinoderms > other crabs > Alpheus > Porcellanidae crabs > Anemone-Sponge > Portunidae crabs > Grapsidae crabs] The highest frequency of macrozoobenthos was in winter and the least in the spring. The mollusks are abundant in two stations and three seasons. These are aggregated on cobble surfaces during winter for foraging and breeding. The wave action in the rainy months and the time in which these are out of water, also behavioral variations have influences on the spatial patterns in gastropods. The lower tidal zone showed more taxonomic similarity by habitats for distribution of macrozoobenthos, especially gastropods. The pattern of mollusks distribution increased from the upper tidal zone to the lower tidal zone. The distribution of other taxa-groups was more density in the middle zone. Golestan and Rostami stations were similar by the cobble coverage substrate so presented close abundances and structure of macrofauna. In order to values of Shannon's diversity index, were calculated in the stations (H'=0.6 Golestan and H'= 0.7 Rostami).