this is due in the main to sedimentation pollution and overfishing these practices have now spread to the high seas where if left unchecked are likely to result in the commercial extinction of a significant number of fish species including many that are crucial for the sustenance of millions of people the european commission estimates that for stocks with sufficient data for assessment per cent are exploited unsustainably with per cent outside of safe biological limits a review of stocks managed by regional fisheries management organisations rfmos found that per cent were overexploited or collapsed