Geography Reference
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ing, and no doubt provide just the kind of nutrition needed by lactating females: maternal
groups (i.e., those including calves and yearlings) spend almost the entire growing season
perched in these hanging valleys, close to the talus slopes of the peaks, feeding on these
meltwater-fed meadows. When these sedges cure in autumn, wild yaks have abundant
grasslands (dominated by nutritious species in the genus Stipa ) just below, which maintain
forage quality far longer each season. Finally, in the harsher winters, these yaks can move
only a few more kilometers north to much more arid grasslands, where although forage
quality is no doubt lower, snow depths are also more moderate.
However, these ideal habitat conditions can also be found elsewhere—particularly
further east within the Kunlun Shan, and further yet southeast in Qinghai and east-central
Tibet, where moisture and lush grasslands become increasingly abundant—but wild yaks
here are scarce if present at all. There must be another reason why wild yaks have done
so much better in Yeniugou than elsewhere, and I think it is this: although Yeniguou's
wild yaks have always had to deal with pastoralists and livestock, they have never had to
deal with high densities of either. And from approximately the 1950s, they have not had
to compete with their domestic descendents much at all.
In Jianshe Township in Aksai County, Gansu, a small population of wild yaks has held
on. Located in the much drier western Qilian Shan (where mesic sedge meadows are
rare), intrinsic habitat conditions are not nearly as conducive to a large wild yak popula-
tion as in Yeniugou. But it is noteworthy that, as in Yeniugou, domestic yaks are absent.
In contrast, the relatively lush pastures in the upper elevations of Gouli Township, about
410 kilometers eastward along the Kunlun Shan from Yeniugou, still appear capable of
sustaining a healthy wild yak population. And indeed, wild yaks were present in Gouli
as recently as about fifty years ago. But now, when I look at the mountains of Gouli with
my Yeniugou-trained eyes and search for places where wild yaks would be at home, I
find that these sites are inevitably occupied by domestic yaks.
Domestic yaks, unlike sheep and goats, are tended loosely, and sometimes hardly at
all. Of course, milking yaks are kept close to dwellings for their daily production of milk.
But most domestic yaks are left to graze freely, often unattended for days or even weeks
at a time. As such, they are free to follow their genetic instructions, moving according
to the underlying patterns of forage availability and quality. Groups of domestic yaks
place themselves on the landscape very much as their wild ancestors would have done.
From a distance, such groups of domestic yaks appear just as do wild yaks, the primary
distinction being that, unlike their wild ancestors, domestic yaks generally come home
when requested. Domestic yaks are raised in northern India, northern Pakistan, in parts
of Kyrgyzstan and Tajikistan, and in Mongolia; they are the mainstay of most pastoralists
in Nepal and Bhutan. But over 90 percent of the world's estimated population of some
14 million domestic yaks inhabits western China, 110 making the Tibetan pastoral lifestyle
possible (and the future of wild yaks uncertain).
The history of yak domestication is shrouded in mystery: we know that Tibetans domes-
ticated them long ago—indeed, Tibetan culture scarcely seems possible in the absence of
the domestic yak—but ancient Tibetans wrote few history topics, archeological research
on the Tibetan Plateau has been limited, and distinguishing between wild and domestic
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