If the question is "has a person walked in these woods," direct evidence of the fact would be a photo or video of a person walking in those woods. Human footprints would be circumstantial evidence that a person has walked in those woods.
I have no direct evidence that there is a beaver or beavers living along the canal trail North of Waterford. I've never seen the beaver or beavers. Although a Waterford Policeman on a bicycle tried to point the beaver out to me once, I couldn't see it.
I do, however, have circumstantial evidence of beaver presence in the neighborhood. A lot of circumstantial evidence. These are all from this morning as I was walking the canal trail, avoiding the organized hike on Peebles Island. All made with my EOS 5D Mark III and EF 70-300mm f/4-5.6 IS USM lens.