'Only 50 years left' for sea fish

The last century of wild sea food

1. Experiments show that reducing the diversity of an ecosystem lowers the abundance of fish

2. Historical records show extensive loss of biodiversity along coasts since 1800, with the collapse of about 40% of species. About one-third of once viable coastal fisheries are now useless

3. Catch records from the open ocean show widespread decline of fisheries since 1950 with the rate of decline increasing. In 2003, 29% of fisheries were collapsed. Biodiverse regions' stocks fare better

4. Marine reserves and no-catch zones bring an average 23% improvement in biodiversity and an increase in fish stocks around the protected area