Seriously, keep yaw distance, and DON'T bring/use ANY plastic bags. Most monkies associate ANY kind of plastic bags on visitors with food, and that's when they can charge and rampage.
Also, raising your voice, stamping the ground etc only excites them more macam you inviting them to fight.
I won't advise you what is the number one element all natural animals fear, but best is to just avoid trouble and stay further away from the trees.
OOPS! Zaccy oredi say about plastic bags. Hehehe...