Lake Nasser, behind the High Dam at Asswan on the Nile River in upper Egypt, began to fill in 1964. Presently about three-fourths full, the 300 km. long lake has a surface area of about 3800 km.?. There are indications that the level of the lake may tend to fluctuate 5 to 10 m. annually around its present stage which may be maintained more or less indefinitely. The lake is basically rich, and local Nile River fish species have established themselves well in all major habitat zones except, because of summertime thermal stratification and hypolimmion stagnation, the deeper water. The principal fishes in general magnitude of abundance are tilapia (very largely T. nilotica), tigerfish (Hydrocynus forskali), three species of Alestes, cyprinids, and siluroids. The commercial fishery now takes about 7100 metric tons of fish, mostly of tilapia, Alestes, cyprinids, siluroids, and Nile perch. It is primarily a rowboat, shoreline, gill net, and trammel net fishery, thus the large stocks of tigerfish and Alestes in the open waters are largely unexploited. Nearly all tilapia and Nile perch are sold fresh while other species are usually marketed in a salted condition. Full development of the fishery shall require more open water fishing, in larger than conventional boats, and with some modifications of existing gear and methods. There is a need for improved processing, holding, handling, and shipping methods.
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