To investigate the ecological impact of a new species of crayfish on the River Nile ecosystem and how it may be positively used. The project will develop a computer simulation model incorporated into a GIS system which will be used to predict the future impact, distribution, and spread of crayfish in the River Nile. It will also investigate the potential use of crayfish in combating Schistosome Vector snails, to promote use in the animal-feed industry, and to assess the economic consequences of crayfish for fishery resources, draining systems, and levees. A small book will be published about the introduction of crayfish to Egypt, and the positive and negative consequences of this action. Making fishermen aware about the positive aspects of crayfish will also be addressed.