Public land is hard to hunt, I tried it several times here in IL and never even saw a deer. There were plenty of tracks and I occasionally saw a deer in the area driving out an hour or two after sunset. The sign I saw in that area was undeniable though; heavy trails, fresh tracks, rubs and scrapes, there were plenty of deer there. One thing I never found was bedding areas. I'm guessing that the deer had heavy hunting pressure every day, in fact I know they did. The area I hunted required hunters to sign a log and there were always people hunting there besides me. Three and one half months of pressure every year had made the deer totally paranoid, they came out at night then crawled into the thickest, thorniest, crap they could find during the day. I'm sure many people forsake that public ground to this day because hunting it is so difficult. The problem is hunting pressure though - not overharvest.
Same thing happened on my farm. 2003-2004 and 2004-2005 seasons I was seeing fewer deer on the back of my property. I was wondering if I was hunting it too much, putting too much pressure on the deer. I tagged deer both seasons, but I wasn't seeing the numbers I had in years past and deer weren't using their usual travel routes. Then one day I caught a guy tresspassing, a light bulb went off, I wasn't hunting the ground any different than I had in the past, outside pressure was causing the deer to vacate the area. A call to the game warden and a few busted poachers and now this year I'm up to my neck in deer again.
Bottom line is humans aren't very effective predators when given a limited season. Too many people claim that the game departments aren't making accurate counts or aren't providing enough hunting opportunities to their residents. Chances are too many hunters have educated the deer for too many years. The deer are still there if there is good habitat, they just know how to dodge hunters. Another point - if more deer are killed in an area than usual they are usually the younger deer(the easiest deer to kill) and the deer that are left are the smarter, older, harder to kill deer.