Two things that go through my mind when I am on a stalk.....
ONE, these animals have no "schedule" all they have to do is eat and drink and survive. No soccer games to get to, no meetings, no work, etc. No spouse nagging them.....
TWO, which plays into ONE, these animals have to deal with the likes of Cougars stalking them among MANY other things. Think your senses are keen? What do you think theirs are like?