At altitudes between 3500 and 5000 metres sheep and especially yaks
graze on the slopes of the Himalaya.
Yaks supply the subsistence of the semi-nomadic stockbreeders. Yak
hair is spun into weatherproof tents, meat is eaten or traded for rice,
and milk is processed into butter and cheese. Yaks carry heavy loads
or pull the ploughs on the small fields of the highlanders. Dried
manure is used as fuel.
In the summer the shepherds live in tents made of black yak's hair,
while the winters are mostly spent in small houses built of stone,
which are also used for storage.
In October, before the passes become blocked by snow, the herdsmen
wander down into the central valleys where they trade dairy produce
for corn and tools.
Whereas in former times business was transacted by barter, today the
money economy has increasingly supplanted the old system.
Most stockbreeders own their own herds; but some keep the herds for
townspeople or for well-to-do farmers from the fertile valleys.
The Tongsa dzong is one of the most important and most powerful monastery fortresses in Bhutan. The designated successor to the Bhutanese throne traditionally carries out the function of governor of Tongsa.