Another possibility would be to go "Boomhower" (from King of the Hill) on him.
a long string of indistinguishable words, slip in a "wife went crazy" a few more indistinguishable words, "got a shovel" a few more indistinguishable words, "blood all over my truck" a few more indistinguishable words, "had to get outta there" a few more indistinguishable words, "sure is a peaceful night to be fishing huh?"
One possibility is act gay and pretend you're coming on to him. but, I'd be very careful with this one, as it may backfire on you, if you run into a couple of the guys here.
Anything that makes them think you're "out there", should work. A new one I'm considering to try next time is to start talking like I am on a cell phone with ear piece, have a nice conversation about fishing and the tide, then turn around to talk to him, waiting for his reaction when he realizes I dont have a cell phone..... If he ask who I was talking to, I'll reply it was my Grandfather who "used" to fish in this spot when he was alive. Talking with the dead, should cause him to give me a wide berth.
It's a lot of fun when you pull something like this off and it gives you a story to laugh about later on with your buddies.