More than 5,000 people are to be relocated to protect a colony of red-crowned cranes, an endangered species with a worldwide population of only 2,000.

The bird is an important symbol in Chinese mythology, representing longevity and immortality. A common image in Chinese art depicts a hermit or reclusive scholar who cultivates bamboo and looks after cranes.

Zhalong National Nature Reserve in Heilongjiang province, which covers 210,000 hectares, is China's largest artificial breeding center for the cranes and home to 20 percent of the global population.