ORIGINAL: hardcorehunter
Actually I feel that on most of my 8 bear hunts that I have been on, the bears all pretty well knew I was there and they just tolerated me. I have gotten way high and they still just know that a hunter is there IMO and many of my other bear hunting friends' opinions. You are right about the sneaky aspect of their behavior; blink your eyes and they are there. Many times I have never heard them and as if by magic, they have appeared.
My brown bear knew I was there, he looked right at me while I was at full draw holding on him at 17 yards, he just didn't know what I was and being that I wasn't another brown bear he didn't perceive a threat and went about his business taking that last fatal step that exposed his vitals.
The black bears I've been around have been hunted enough that they won't tolerate any presence of anything around them (they've been getting beat up by other black bears, brown bears or shot at by humans) when they sense something is up, they're gone.