This has been a hell of a morning. Since Kitty had an appointment for major oral surgery, we were up at the usual time. The routine was the same. I let all 5 pets out and went to have breakfast. Just before we were about to leave for her appointment, I heard Mesa barking in the yard. I went out to see what he saw and found him staring intently up at the mesa. That usually meant that someone was jogging with their dog. I didn't see anything. Suddenly I saw 2 things running down the mesa. It happened so quickly I couldn't tell what they were. I did, however, hear a cat scream. I instantly opened the gate and Mesa bounded up the hill. He gave chase to something. I couldn't see because I ran inside to get my shoes on. I hiked up the mesa expecting the worst. I scanned the ground for blood. Nothing. I got to the top and looked around. Nothing. On my way back down, however, my heart sank. There was Billie in the middle of the path panting furiously and mewing pitifully. I grabbed her and headed back to the house. She was visibly shaken but there didn't appear to be any wounds. I took Kitty to the dentist and Billie to the vet. She got an exam and was found to be no worse for wear. She lost a tooth in the fray and had a small puncture wound on her back, but other than that she appears to be fine. She's limping a little bit, but nothing is broken. So I don't know if it was a yote or another dog, but she was saved by Mesa. I love having such a fearless pup.