Yesterday I was asked, as a scientist and field ecologist if I believed in spirits in the forest. I replied, "Definitely, there's a lot of weird shit that goes on in rainforests." It isn't just me, all my colleagues have similar experiences.
When I train new students, I always make it a point to tell them about the 'adat' or taboos whenever entering the forest. You are entering someone's house, so you better behave. A forest must be respected, otherwise it plays tricks on your mind.