Seldom seen, the detail of their lives has long been a mystery,
but now, at last, helped by the latest remote-camera technology,
we are getting closer to them than ever before.
They are very rare, only about four of them in 40 square miles.
There is simply not enough prey to sustain more.
They live solitary lives.
Nonetheless, they are well aware of the presence and the movements of their neighbours,
because they leave messages in a few special places.
They rub particular rocks with their cheeks and then spray them with urine.
The two perfumes create a unique signature.
Any other leopard can know which of its neighbours passed this way, without ever making direct contact.
But there are times when snow leopards must come together, and the event is often violent.