ABSTRACT
Fish can provide protein at half to two-thirds the economic cost of mammalian protein. Environmentally, freshwater fishery projects are among the most desirable for vertebrate protein production. Fishery projects are vulnerable to pollution, civil works such as hydroelectric projects, irrigation schemes involving water diversion and sedimentation, and hydrological changes brought about by deforestation. The culture of fish in waste water treatment lagoon systems generally results in effluents of higher quality. In Southeast Asia, brackish water fishponds in estuarine swamp have been created at the expense of mangroves and their associated wildlife. Herbivorous fish have been successful in controlling the proliferation of water weeds. Fish migrations are often impeded or even prevented, habitats are modified or eliminated, and water quality may deteriorate in reservoirs. Environmental aspects of fisheries projects include watershed and coastal zone management, artificial stocking of fish in rivers and lakes, improvement in present resource management techniques, and use of surveillance techniques to prevent Overexploitation.
