First try putting a radio out there, seems to help a little with keeping the critters away, exspecially my favorite enemy the Raccoon.
Second, I have a mean rooster as well, what I have been doing is you pull on his waddles. YEH, you can't negotate with them, but tugging on the waddles put you in CHARGE. Thats the only way I found out that works, it takes a few tries before your rooster will get the hint and make him think : "if I peck at her, she's going to tug on me, hell NO". My mean rooster's will now look away when I'm near instead of pecking at me.