Did you try any attractor type flies? I'd try something like a stimulator or royal wulff....basically, a flashy fly that also looks somewhat "buggy". In the event this doesn't work, bring along a bag/satchel to carry some rocks in. I'd use some golfball sized rocks (you don't want to KILL the fish, just scare them), and toss them gently, so they don't bounce off the other rocks and come shooting back at you. Also, use your non-casting arm, so your free to cast to the fish when they get within range.

Regards,
Joe Martin
Salem, OR