Oh they know when the season starts and ends! Last year as my hubby and I exited the woods at dark on the last day of rifle we looked across the hill to see a whole herd of deer prancing, jumping, running. I swear they were having an end of season party!!!
On another note, where my brother hunts he always flushes out this buck that beds right next to the barn in some thick brush. The barn is not used for anything but storage right now but there are plenty of people near it every day. The buck knows he is safe right now. But I guarantee he won' t be hanging out there next month.
I think after a year or two they sense a change in the season and the dangers that come along with it. Maybe it is a new scent on the humans that triggers it - I think it is Whitetail Fever!