Three-quarters of the world’s fish stocks are currently exploited to the maximum extent, if not in excess (FAO, 2000). This exploitation has had the following impacts:
A growing variety of fishery products are being exploited. Commercial fishermen are targeting progressively smaller species at lower levels of the food chain because the main predator species are being depleted.
Most of the world’s main fishing areas are close to full exploitation. The eastern Indian Ocean and the western central Pacific Ocean are the only areas that still show little sign of stress, and which exhibit a potential for continuing growth (FAO, 2000).
The northeast Atlantic Ocean continues to exhibit declining catches, as well as a shift towards fish at lower levels in the food chain. Indices developed to monitor changes suggest that continued heavy fishing may lead to irreversible ecological change.
Rivers, lakes and wetlands, which account for less than 1% of the world’s surface, but at least 8% of its fisheries production, are under mounting pressure from the growing human population (FAO, 2000).