The raised crane booms at the ports of China’s Pearl River Delta are a sign of the behind-the-scenes drama in global outsourcing.

The booms have often been raised out of use since early in 2008, when the Chinese authorities launched a crackdown on labour standards in the area, which had been the first beneficiary of China’s manufacturing boom. Production, and port activity in coastal cities such as Shenzhen, shifted to elsewhere on China’s coast or even to other countries.