Fish have long provided an important item in the diet of Amazonians, but ecological and cultural changes threaten the long, term productivity of aquatic ecosystem. Population growth, the opening of extra-regional markets and the introduction of new or improved technologies, have increased pressure on fisheries of Amazonia, the worlds largest freshwater catchment. Habitat destruction due to agricultural expansion and development projects also threatens to undermine fishing yields. Modern conservations practices, such as the establishment of parks and reserves and the enactment of protective legislation, are only gaining a tentative foothold in the region.