Approached by older guys.

Hey everyone, I was at my local nude area on the weekend, its a tea tree lake which sits behind the nudist beach area. Its clothing optional and i had been swimming there and got out to dry off when an older guy tried hitting on me and asked if i wanted to  take a walk in the bush. I am straight, 19 and most of the time go alone, but i don't think this is acceptable, it made me want to leave, which i did. Anyone else have any similar problems?
Im currently looking for mates to share these trips with, and having company would also deter these pervs.