^^ On Utah, I have read that the area around the headwaters of the Weber River is a BF hot spot.
I always wanted to visit the lakes above the area and then head down into Weber canyon, but had not had the time.
Have you ever visited that area?
I did have an encounter with an unknown creature by Butterfly Lake campground over 10 years ago (an area close to that Weber drainage).
Can't call it BF, but whatever it was, it was making loud guttural sounds (that woke me up) and throwing little sticks, pebbles or nuts at my tent in the middle of the night (so many that I thought it was light rain).
The creature woke up a dog that was with other campers down below us (~60-80 ft away) but my friend camping in a tent next to me slept thru it (despite the guttural sounds, dog barking, and me yelling to wake up).
I never got the courage to get out of my tent. In retrospect, I don't know why I just did not check what was making those sounds and throwing little pebbles/sticks at my tent.
Instead, I went back to bed and ignored it.
I have friends who had an encounter in one of the southern canyons into the High Uintas and on the eastern edge of the range by Flaming Gorge. So the place has presence.