As the top carnivore of the alpine and subalpine zones, the snow leopard strongly influences the numbers and whereabouts of hoofed herds over time. That in turn affects plant communities and thus shapes the niches of many a smaller organism down the food chain. The leopard's presence—or absence—affects competing hunters and scavengers too, namely wolves, wild dogs, jackals, foxes, bears, and lynx. This cascade of consequences makes Uncia uncia a governing force in the ecosystem, what scientists term a keystone species.
Since the range of the snow leopard overlaps those of so many other creatures, protecting its habitat also preserves homes for the majority of mountain flora and fauna. While we were exploring part of the Zanskar Range in Ladakh, Raghu and I crossed tracks that sent him racing off to an overlook. A few minutes later, a brown bear—the same species as North America's grizzly—galloped and slid down a high riverbank, swam across surging rapids, muscled halfway up a cliff wall, and finally lay down to dry its silver-tipped fur in the warm morning sun. We had found one of the last few dozen of its kind in that huge section of the Himalaya.
Do snow leopards attack humans, as bears sometimes do? No, never, Raghu says. He once watched a village girl pulling on one end of a dead goat, unaware that the other end, hidden by a bush, was snagged in a snow leopard's jaws. She came away unscratched. But a single leopard swatfest in a herd of livestock can plunge a family into desperate poverty.
Because farming is marginal at best in Central Asia's cold, dry landscapes, traditional cultures depend mainly upon livestock to get by. Some herders operate from mountainside hamlets. Others are nomadic, migrating long distances between seasonal pastures. Either way, snow leopard conflicts come with the lifestyle. Wired to select the unwary and the stragglers among wild ungulates, the cats can hardly help picking off a few domesticated versions. At night, when flocks are stuffed into low stone corrals, a leopard can all too easily hop in to join them.
During a several-day trek through the Sham area of the Ladakh Range, which rises to the north of the Zanskar Range, on the other side of the Indus River Valley, Jigmet Dadul, a conservationist, and I made our way over the passes to the barley fields and poplar groves of the village of Ang. There we looked up Sonam Namgil. Three nights before, a snow leopard had leaped atop his stout mud-brick outbuilding and then ten feet down through a ventilation hole onto the floor. When Namgil opened the door in the morning, he found wide golden eyes staring back amid the bodies of nine goat kids and a sheep.