I have no idea. It was a fleeting view. My immediate response was to think I was seeing a large dog (about the size of a black alsation). Then it got up and walked away, and its movements were undeniably feline. The friend I was with and I argued for ages over whether we had seen a cat (it was too big) or a dog (it was too feline). Weeks later she turned up the fact that big cats have been sighted in the area for ages.