Banner
عربيHome
Biodiversity Habitats & Flag species Wild Life Eco-tourism & protectorates Indigenous people Conservation
Gebel Elba
Mountains and Wadis of the Eastern Desert
Red Sea Littoral Habitats
Red Sea Islands
Red Sea Marine Habitats
Mountains and Wadis of South Sinai
Central and North Sinai
Mediterranean Wetlands
The Nile Valley and Delta
Gebel Uweinat and  Gilf Kebir
Sands and Dunes of  the Western Desert
Western Desert Depressions and Oases
Western Desert Mediterranean Coast
Mediterranean Marine  Habitats
 

Coral reefs are among the most important of all marine habitats and the Red Sea provides ideal environmental conditions for stony corals of which over 200 species are found in this semi-enclosed sea. The shallow shelves bordering the sea ensure sufficient light for calcification to occur and for photosynthesis in the algae on which some polyps feed. The more delicate branching corals thrive in shallow, well-lit water. More massy corals do well in deeper water and are better able to tolerate suspended sediment, which both cuts down available light and tends to clog the little polyps. Corals that are more efficient at cleaning away the sediment do better in areas of relatively high sedimentation.
            Symbiotic algae that grow only on live corals produce part of the food the polyps need. Other algae growing on reef faces are food for herbivorous fish and other creatures.
            Most stony corals are reef-builders, generally colonial. Each polyp builds a skeleton and the animal sits in a calcareous cup, or theca, that it has secreted. The polyps are connected to each other by an extension of the body above the level of the skeleton. Thus, the colony sits on the surface of the skeleton. In some species, the polyps are widely separated and form branching structures; others are close to each other and have thecal walls in common.
            Coral polyps reproduce by means of asexual budding in order to form and enlarge the colony, so colonies can often extend over large areas. The growth rate for some stony corals can be as low as 1cm a year, however, the rate at which coral colonies grow depends on the type of coral, the location and the amount of sunshine they receive. Some corals grow at a rate of 20-25cm per year in very good conditions. Others are slow growing at 4-5cm per year under very good conditions. Under normal conditions these rates are halved. Breaking off just a few centimeters of coral to take as a souvenir can mean breaking off many years of growth.
            Coral reefs provide habitats for many plants and animals. They form an ecological niche in which creatures can live, feed and take refuge from predators. Crustaceans, worms, starfish, and fish all benefit from the coral reef ecosystem.
Called sea grasses because they grow in small lawns or meadows and for the long grass-like leaves of many species, these aquatic plants are more closely related to the pondweeds than to the huge family of grasses. Sea grass beds occur on the shallow coastal shelves of the Red Sea and contain eleven of the limited number of species known worldwide. Due to the relative lack of suitable shallow, sedimentary habitat, the number and size of these beds is limited. However, the ecological importance of sea grasses may be comparable to that of the reefs as they are among the richest and most productive of marine ecosystems.
In the Gulf of Aqaba, 49 species of invertebrates were found living in the sea grass beds, of which about 70% were mollusks. About 9% of the species living in these beds were found in no other habitat. Sea grass beds are important providers of food, shelter and protection for the juveniles of various species of commercially important fish and crustaceans and are the only source of food for the Green Turtle, Chelonia mydas, and the Dugong, Dugong dugon.
            It appears that the diet of this large marine mammal consists entirely and solely of one species of sea grass, namely Halodule uninervis. It pulls out the grass, using its flippers and makes it into several stacks; it then eats the stacks in more or less serial order.
            Offshore waters: Corals and sea grass beds are found in the shallower waters of the Red Sea but the deeper waters are also home to a great diversity of fish that feed on plankton, invertebrates or each other. Among these, the largest and most well known are the sharks of which several species are found in this zone. Cetaceans are also not uncommon in Egyptian waters and include Risso's Dolphin, Grampus griseus, and Bryde's Whale, Balaenoptera edeni

 
First Back 3 of 6 Next Last
Sohal Surgeonfish, Acanthurus sohal

This beautiful and colorful fish is a very aggressive territorial species that is characteristic of coral reef habitats. It gets its name "surgeonfish" from the razor-sharp, hinged spine that folds into a groove on each side of the peduncle. It can slash other fishes, or a human who tries to handle it, with a side sweep of its tail.