if I read it right you dont even own the 2 acres the guys hunting on correct?If thats right he has every right to be there and unless you physically catch him in the act of tresspassing he isnt doing anything wrong.
I dont know the tresspass laws pertaining to wounded game where you live but here if I shoot a deer and it gets on your property I have every right to go in after it without notifying you as long as Im not armed while doing it.If I do notify you and you say no Ill go in anyway and bring a warden along with me when i do it.
You could do as the previous poster mentioned and start screwing with his hunting while hes in there but your gonna be wasting all your own hunting time trying to keep him from hunting and many states now have laws against interupting someone who is legally hunting and you may well wind up with harassment charges if you push the issue and screw with him to much.
Personally i would enjoy the 88 acres you have to hunt and not worry about the guy on another property unless you actually see him do something wrong.