Pareidolia is a problem with so many perceived Bigfoot reports to the point where it's a concern. The first thing you should verify first when seeing a large hairy beast is if it's a bear. But some still argue it's not a bear...
From the book: "Encounters With the Strange and Unexplained" by Matt Hoyle.
"We were in the car going backpacking and pulled off the road to let the dogs get a drink in the river. We were watching the dogs play when Keith said, 'Oh, there's a bear.' But I thought it was a fisherman. So we just stood there arguing about it for a little while. Then the figure started to move and pull itself with its right arm. It stepped up a huge embankment and disappeared into the tree line. I remember this super—big arm just kept reaching up further than any human arm could have gone. We looked at each other and just went, "What was that?"
Wendy and Keith