Biodiversity of Some Invertebrates of Mangrove Ecosystem in South Sinai, Egypt

Abstract

A field survey was carried out on the macro-invertebrate fauna of the mangrove ecosystem in Ras Mohamed and Nabq Protectorates in South Sinai, Egypt, during the period from June 2013 to May 2014. The studied area of Nabq known is as Wadi-Kid, it has four sites of mangrove: El-Gharqana, Arwashia, El-Manqata and Abu Zubad.Changes in water surface temperature, air temperature, pH, the concentration of dissolved oxygen, salinity and types of habitats were recorded.A total of 122 species from the five sites of study were recorded; these species are belonging to the following phyla of invertebrates: Cnidaria, Crustacea, Mollusca and Echinodermata. The highest number of species was represented by molluscan invertebrates, dominated by 108 species followed by Crustacea with 11 species, Echinodermata with two species and finally the Cnidaria which was represented by one species. The highest diversity of species was recorded from Nabq at El-Gharqana site (92 species), followed by Abu Zubad (67 species), El-Manqata (57 species), and Arwashia (49 species). The number of species recorded from Ras Mohamed was 55 species. The pattern of distribution of the species in the present work was different from one site to the others.The status of the recorded species in such specific habitat was markedly variable from phylum to another.A total of 29087 specimens of all species were recorded from the different sites during this study. Out of them 21910 specimens (75.3%) were Mollusca, 6792 specimens (23.3%) were Crustacea, 257 specimens (0.9%) were Cnidaria and 128 specimens (0.5%) were Echinodermata. The macro-invertebrate groups exhibited marked seasonal variations in their occurrence in the mangrove sites at Ras Mohamed and Nabq Protectorates. The population density and species richness of macro-invertebrate species in different seasons were recorded in mangrove sites of Ras Mohamed and Nabq Protectorates. Some groups exhibited clear zonation in distribution, others were just visitors but the majority was resident in the mangrove. The highest similarity in the distribution of macro-invertebrates was 69.18%(between El- Gharqana and Abu Zubad), while the lowest similarity was 48.28%(between Arwashia and Abu Zubad). Key words:Macro-invertebrates, mangrove, South Sinai, Cnidaria, Crustacea, Mollusca, Echinodermata, distribution, status, seasonal variation, population density, richness, zonation and similarity.