It is still not clear why the animals were dumped in the river in the first place or who was behind it, says the BBC's Martin Patience in Beijing.

BBC: China fishes over 2,000 dead pigs from Shanghai river

He said after being rescued from the river Mr Oldfield was detained by police who asked him why he had jumped in the water.

BBC: Trenton Oldfield 'caused chaos' at University Boat Race

Bishop Cappio wonders why water is being exported when 3m people live along the river's course, many of them poor and without plumbing.

ECONOMIST: Brazil's S?o Francisco river project

So why did the industrial revolution begin in Britain and not along the Yangzi river?

ECONOMIST: China's future

Immediately, the henchmen of evil boss Grayle take Rory hostage (I had to dig deep to find out why: It turns out that Grayle was actually taking River hostage but Rory got in the way).

FORBES: Doctor Who 7.05: The Clock Winds Down for Amy and Rory

The framework on which this is all hung is a historical look at the expansion of surfing from its roots in Hawaii, and exactly how and why it spread to certain sometimes bizarre places, always eliciting passion along the way, like river surfing from dam generated waves in Germany to Cuba, Japan and the Middle East.

FORBES: How Surfing Explains The World?

That is one reason why in April Metsa-Botnia, a Finnish company, began building a cellulose plant on the Uruguay River bordering Argentina.

ECONOMIST: A battle over foreign investment