Dead guitarfish, rays, and other species are tossed from a shrimp boat in the Gulf of California, Mexico. Tons of fish are thrown back to sea every year. International attention to wasteful fishing methods have resulted in relatively new net and hook designs, which prevent some bycatch. "Overfishing has been historically [the] oldest and [most] major threat to ocean life today," says National Geographic fellow Enric Sala. Brian Skerry / ocean.nationalgeographic.com

By Richard Black
14 April 2011 Just how …….d are the world’s oceans? I’ve put the dots in that sentence so you can insert the word of your choice. According to a high-level seminar of experts in Oxford earlier this week, there’s one word starting with the letter S that would fit quite well, a longer option beginning Kn – and a few more that are even stronger in meaning. The S option, by the way, is not “secured”. Scientists are famous for staying in silos and never peering over the edge at what’s going on in the world around them. What marked this week’s event – convened by the International Programme on the State of the Ocean – as something a bit different was the melange of expertise in the same room. Fisheries experts traded studies with people studying ocean acidification; climate modellers swapped data with ecologists; legal wonks formulated phrases alongside toxicologists. They debated, discussed, queried, swapped questions and answers. Pretty much everyone said they’d learned something new – and something a bit scary. … In places, filter-feeding fish are apparently living in sediments containing so many particles of plastic that it makes up half of each mouthful. Other pollutants such as endocrine-disrupting (“gender-bending”) chemicals gather on the plastic surfaces – which obviously can be harmful to the fish. … Many researchers noted that in their field of study, the pace of decline and degradation exceeded even the worst projections made just a few decades ago. … And here lies the biggest challenge for this project – especially in a world where the number of “other Cassandras”, to use a phrase from the JM Kaplan Fund’s Conn Nugent, appears to have grown way beyond the public’s appetite for messages of doom. … When the final report is written, its conclusions are likely to include (however worded) a warning that the oceans are in deep trouble, that decline is speeding up, and that impacts of this are already being felt. …

Exploring the ‘oceans crisis’