Years ago, my Club had a campout with a bunch of shooting contests. Most were the usual; one shot, two hundred for score, five shots for group, that type of thing. But one event was the running fox, a plywood cutout of an archery target, with two eye bolts screwed into the top. The operator was up on the hill, out of sight and you had some warning, and a specific window of opportunity between two large pine trees. Two shots, IF you could get them off; and only a few did. Many of the guys were casual about it, and when that target came sliding down the wire, they weren't as ready as they thought they were. You could see that everybody was hitting behind it. Didn't matter to know that, they still missed behind. At the end of the day, about fifty contestants, there where TWO holes in that board, and these guys were all experienced predator hunters? I (quite modestly) mention this to illustrate the difficulty, in general, and the fact that I still have that second place trophy in my closet. If my shot had been an inch further back, I'd have missed too! The winner was dead nuts; I choose to think he was just lucky. 
But, I like what Craig has to say, because you can't be intimidated by it, or you are going to just let them ride on out of there. If you are really sloppy, and fear the bad hit, I suggest jackrabbits as worthy practice. But, if the fear, or self doubt, or whatever label you put on it, is overwhelming, don't do it. If you don't have a stationary shot, and you can't, or don't know how to stop him; forget about it, and move on to the next stand.
I will say this. I know a couple knowledgeable shooters, (who shall be nameless, to protect.....me!) all the technical gear known to the free world, and they are both remarkably poor field shots. I think it's intimidation, they choke on fur, every time. One can't hit nuthin' and the other guy drives you nuts, he can't pull the string.
Good hunting. LB
