A slight catch: Thailand's overfishing crisis

It's almost midnight, 10 kilometres off the west coast of Thailand, and Thamarat Sachanyarat has been circling for hours, carefully watching the swirling patterns on his boat's sonar. Peering closely at the monitor with failing eyes, the 54-year-old sighs and pushes the throttle, moving his wooden fishing boat on to a different patch of sea.

All around, the lights of dozens of other boats can be seen in the pitch-black night, each crew in pursuit of a resource that is fast shrinking in the face of massive overfishing.

"We are all worried about overfishing. My grandfather would use a torch and shine it into the sea, and the fish would come to the surface. It was like the sea was full," says Thamarat, wistfully.

He uses high-powered lights to draw the fish to the surface, to be scooped up in giant nets that take a dozen or more crew members to haul aboard. It is a decidedly commercial operation; if he and his crew don't return with at least 1,500kg from each trip, they lose money.

Thailand is the world's third-largest exporter of fish and fishery products, with exports valued at about US$7 billion in 2010. Between 2002 and 2011 exports almost doubled. Only China and Norway export more.

Taking into account the sheer volume of fishing that has taken place off Thailand over the past few decades, improved technology that until recently increased the size of catches, and what most consider to be an impotent regulatory system, it appears the nation's waters are reaching a critical time, with some species nearing the point of no return.

"The Gulf of Thailand is one of the most exploited seas in the world when it comes to fishing. Compared to a few decades ago, in the Gulf of Thailand there are pretty much no fish," says Sirasa Kantaratanakul, oceans campaigner for Greenpeace in Thailand.