Sheep cross frozen lake from island pastures

For thousands of years shepherds have taken their herds to graze in winter and return in early spring

Moving livestock to pastures in the depths of winter is tough. However, traveling across a frozen lake with thousands of sheep in tow poses an even greater challenge, and that is exactly what herders face every year on Puma Yumco, one of the world's highest bodies of water, located in the Tibet autonomous region.

At Dowa village, 5,070 meters above sea level, thousands of sheep are taken across the frozen expanse during the coldest time of the year to graze on a green island in the lake. The herders, who clear a path using cow dung and hot ashes, usually spend a month with the animals on the island, where the grass is waist high.

As spring draws near, the sheep are walked back across the frozen lake before the ice melts. The seasonal herding has taken place in Dowa for thousands of years.