Mountain lion would give me even more cause for pause.
Boarding stable 15 miles from here awhile back said they had eliminated pasture only board and were bringing all horses in the barn at night because a horse had been attacked by what had to have been a couger. Tore up his back. Horse escaped though. They do butt right up to forest land. They aren't common here, but they do exist.
I would imagine you do have cougar up there. Most of the time, they stay away from people but we had one three or four years ago that was walking right through yards. He/she got hit by a car, probably one that was old or ill.