Ranger roams reserve to protect rare golden yaks

With incredible agility, 52-year-old Phurchung rushes through the creeks and rubble on the Changtang grasslands 5,000 meters above sea level, watching over the "golden treasure".

He heads one of 73 management stations across the Changtang National Nature Reserve, covering an area of 298,000 square kilometers in the northern Tibet autonomous region.

The nature reserve is the biggest and highest in China, and is home to a variety of wildlife species. Among these, the golden wild yak is perhaps the rarest.