The process of long and location changes of sea star(Astropecten hemprichi) and sea urchin(Diadema setosum) in the coast of Chabahar Gulf

Abstract

This research aimed to study the process of long and location changes of sea star(Astropecten hemprichi) and sea urchin(Diadema setosum) in the coast of Chabahar Gulf in the Oman Sea, IR. during November 2008 to September 2009. The area of study was at the farthest end of south east of Iran in province of Sistan and Balouchestan. Sampling was done bimonthly during low tide from 5 stations, using 1m×1m quadrating randomly. 1885 samples of Echinodermata were collected and studied. Results showed that 32 of them(1.6%) belong to A.hemprichi species and 28(1.4%) samples belong to D. setosum species. The samples then were counted and identified. Then the samples’ abundance, distribution and stability were investigated. The results show that the maximum abundance of A. hemprichi was occurred in September 2009 (1/92±0/76ind.m-2) and The maximum value for D. setosum was shown in November 2008 (3ind.m-2). Investigation of distribution and stability indicators may reveal that A. hemprichi and D. setosum were dispersed more randomly and they may be considered as the rare species.