Fish diversity in correlation with some environmental factors in the mangal of two protectorate areas, ras muhammed and nabq on the red sea in egypt.

Abstract

The present investigation is an attempt to study the fish diversity at five sites of the mangrove forests (Mangal) in two famous protectorate areas : Ras Muhammed and Nabq on the Red Sea in Egypt. The present investigation revealed that the high salinity and temperature as well as the decrease in dissolved oxygen in Ras Muhammed and Nabq has a profound effect on the low density and diversity of species inhabiting these areas. This study revealed that 22 fish species belonging to 15 families, 12 suborders, 9 orders and 2 classes are represented in the studied areas. Among these collected fish species, 7 species belonging to 5 families, have not been recorded in the studied areas. These fish species are : Atherinomorus lacunossus, Istiblennius andamannensis, Solaria fasciatus, Gnatholepis anjerensis, Istigobius omatus, Siderea picta, andArothron diodematus. Also, the study has revealed that the mangal in South Sinai contains few fish species compared to any other marine habitats. Some of these fishes are economically important. Moreover, the mangal is considered as a nursery ground for many fish species, especially those which are economically important such as, Mugil cephalus and Crenimugil crenilabis ( F. Mugilidae) and Acanthopagrus bifasciatus, Diplodus noct, Rhapdosargus haffara ( F. Sparidae).