The final journey

Every year, billions of birds across the globe follow established migration patterns from north and south. From early October to December, birds from Eastern Europe, Mongolia and Northern China fly to South Asia via the "Millennium Bird Trail" which passes through Hunan and its neighboring province, Jiangxi. Three of the world's eight major migratory routes pass through China.

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The geological conditions in Hunan and Jiangxi make the provinces the only path for southbound migratory birds. "The wintering grounds may vary from place to place, year to year, but the route never changes," said Jiang Yong, who heads the office of the Worldwide Fund For Nature in Changsha, the provincial capital.

Migration is a well-known phenomenon, but scientific research has been unable to provide a convincing explanation of why these "fixed routes" exist, he said. Some experts believe that geographical conditions, wind speeds and air humidity play a key role, while others favor the theory that the earth's magnetic field plays a crucial, if little understood, role in guiding the birds to their winter quarters.

Unluckily for the birds passing through Hunan, their timeworn routes provide rich picking for the hunters. "Most of the birds killed are small and medium-sized," according to Li, who described the flocks as "bird rain". In the period just after sunset, countless numbers of birds fly above the mountain villages where "hundreds of well-prepared professional hunters wait, their lights fully illuminated to attract them. They use guns and homemade cannons loaded with grapeshot that can kill tens of birds in one go."

Once dead, the birds embark on one final journey - to the dinner table. Some of the hunters are so successful that they make their entire year's income during the short migratory season. Diners pay as much as 300 yuan ($48) to eat rare species such as swan in local restaurants. For rural families existing on an annual income of 1,000 yuan, the bird-hunting season is a big deal.

And while some of the birds are sold locally, others are loaded into refrigerated trucks and transported further afield, to places such as Guangdong province, where the locals traditionally have a taste for bird meat.