Red Sea is one of the most unique reservoirs of biological diversity on the globe, with its immensely complex ecosystem and great variety of coral reefs and endemism. The geological episodes and hydrographic conditions lead to species diversity difficult to be matched by other enclosed seas.
The Jordanian coastline that extends for about 180km to the Sill of Tiran in the South. This short coastline is characterized by the availability of different habitat such as coral reef, seagrass beds, deep sea, sandy bottoms, muddy bottoms and rocky bottoms; this certainly will lead to high fish diversity in comparison to other regions, it hosts approximately 500 fish species.
The Jordanian coast extends only for about 27km from the northernmost tip of the Gulf of Aqaba harbors more than 150 species of coral, which support an enormous variety of fish species remarkable in their wide range of color patterns and outstanding beauty. Coral reefs have many functions, amongst which is provision of a variety of habitats for many organisms. Fishes are a dominant group of coral reef fauna, both with regards to their biomass and diversity. This ecosystem provides them with shelter, feeding, spawning and nursery grounds. Also, the Jordanian coast is characterizes by the availability of the seagrass beds at the north and the Big Bay at the south. These areas appear to be essentially important in terms of fishery resource. The reefs and the adjacent sea grass beds harbor an abundance of commercially important resident fishes such as rabbitfishes, goatfishes, and parrotfishes. Fish larvae can settle down in seagrass beds and find food and protection against predators until they are grown up. As juveniles or sub adults they migrate to the coral reef. This underlines the important of seagrass beds as nursery ground for fishes.
Shore fish community structure of the Jordanian Red Sea coast determined on fringing coral reefs and seagrass beds exhibit a total of 198 fish species belonging to 121 genera and 43 families. Labridae and Pomacentridae dominate the ichthyofauna in terms of species richness and Pomacentridae are the most abundant. Neither diversity nor species richness was significantly correlated with depth.
One of our interests in the fish lab also is the fish larvae that settle down in seagrass beds to find food and protection against predators until they are grown up. Once juveniles or sub adults they migrate to the coral reef. This underlines the important of seagrass beds as nursery ground for fishes.
Marine fisheries in Jordan are extremely limited. The current national fish production from fresh and marine water resources is about 300 tons year-1. This comprises only about 1% of the national fish consumption. The remaining 99% are imported indicating that local fish production too short to meet the market demand especially in recent years. This emphasizes the need for covering the shortage in fish production by aquaculture. The coral reef habitat of the Jordanian coast stand as a serious obstacle, because they are sensitive to nutrient enrichment that results from aquaculture. Only well managed and strictly controlled environmentally friendly aquaculture can then be practiced.
Environmentally friendly aquaculture practices have therefore become one of our prime interests. Theses allow for the generation of high-valued commodities without harming the environment. One such approach is the polyculture of species belonging to different trophic levels. In this ecosystem approach, the 'wastes' generated by one trophic level are used as resource for the other. A second approach is the culture of species at the base of the food web, such as algae, macrophyte- and plankton feeders. Such extensive systems rely on ambient supplies of materials and energy and thus produce no excess nutrients. A combination of the two is the mariculture of giant clams (Tridacnidae) which exploits (i) the effective recycling of material between two trophic levels embodied within one organism -the animal host with its algal symbionts (zooxanthellae)- and (ii) the natural supply of energy and material to the clam-symbiont association. Their mixotrophic life-style enables giant clams to tap different nutrient sources and achieve high growth rates in spite of low ambient concentrations. This makes them particularly amenable, conceptually, for integrated farming with other marine ornamentals in closed systems - but to the best of our knowledge this has not yet been attempted. In addition, giant clam farming in particular has not been attempted in the Red Sea area, in spite of the occurrence of indigenous brood stocks of T. maxima and T. squamosa which are suitable for aquaculture. Therefore, we have established a pilot plant for giant clam aquaculture in Aqaba, Jordan.
Green Aquculture and research scope in Aqaba
Neither in Jordan nor other countries are engaged in any of mariculture activity in the Gulf of Aqaba. Therefore, based on the experience gathered, Jordan should practice and implement mariculture technologies for the production of corps to be environmentally safe and at the same time include provision of a new source of high quality product to generate a new source of income for the country from the export. Mariculture has been recognized as an alternative source of sea food and marine ornamentals supply, which showed in recent years significant advances in larval rearing techniques for tropical reef species. The Gulf of Aqaba being subtropical in nature with warm winter temperature dictates that the out door as well as the indoor pond culture is viable for green production and tropical aquaria. Temperature narrow range and the warm to extremely dried climate in summer both could play a significant role in minimizing energy required for green aquculture, the reason that can make large scale experiments to be conducted easily. A major disadvantage of developing mariculture in the Gulf of Aqaba however is the possible adverse environmental impact. Nutrient enrichment in a restricted space, where coral reef is a dominant habitat is a serious concern. Therefore, these activities should consider the impacts on the environment and develop effective measures by practising forms of aquacultur to be environmentally friendly. Therefore, different aspects of culturing techniques of some tropical species is under investigation at MSS. Parameters that included in our investigation extend from the possibility to domesticate tridacna being self-sufficient with regard to nutrition and well-adapted to oligotrophic waters and if possible other invertebrate species from the Gulf of Aqaba. Hence, the provision of successful brood stock could be achieved through the provision of healthy conditions in captivity that influence the state of health and survival of the different cultured species. Physco-chemical and biological characteristics of the rearing sea water in addition to a well-controlled surroundings are essential for efficient production. In the development of green mariculture at the MSS we take into account the establishment of a suitable infrastructure necessary to undertake research in the followings aspects, brood stock conditioning, breeding, larval and juvenile rearing. The aquaculture plant at MSS (above) has been built in a modular fashion, in order to allow for future scaling-up. It consists of a working area including hatchery, an outdoor nursery and two race ways for rearing different marine organisms. In addition, a special building to hold a newly installed recirculating water system .