Where I deer hunt down in Alexander County there was one hit by a train a few years ago. One of our buddies has one on a trail cam just a couple miles down the road from our property. They have seen a cat walk into to woods right where my stand is. I live in Kane County and out behind my neighborhood I have found tracks of the big cats. I know they aren't coyote or a large domestic dog because noone has a dog with a track bigger then my fist in a ball. 280lb guys have big fists too. I find deer kills almost weekly when I'm shed hunting. coyotes dont cover their kills with grass but cougars do and they are usually always covered as well. 5 Miles from my house at a tree farm my buddy has pictures of a mountain lion on his trail cam.
A friend that I turkey hunt with and ocassionaly deer hunt with has seen a document from the 80's which stated there were 2 pairs of breeding cougars placed in every county to keep deer herds down. 2 pairs means 4 cougars and cougars have more the one cub per litter if you will. over the years that number adds up.