I totally think that we have creatures here that are in remote areas where they are seldom, if ever, seen. There are sightings of birds that look like the pterodactyls, or a similar type of what we consider prehistoric birds. Some of the old carvings and clay pottery have pictures of dinosaurs, and also humans hunting them; so I think that we had some of these creatures fairly recently, and might even have leftover ones in areas where humans do not generally go. I do not know how the Bigfoot figures into this, but since the native people have had legends of them , it is not just modern day people saying they exist. In Russia , there is the story of the Bigfoot (have different name there) that was captured and had half human offspring, and there’s are said to be some of her descendants buried in the local cemetery there.
Big Foot must have a metal detector now, note he didn't push it in the south where behind every tree is a gun.
One of the old Elvis jokes (remember some of the conspiracies claim he is not dead) is that he was captured by aliens from space and put in cage with a Sasquatch. The aliens were not too familiar with Mammal biology and didn't know the Sasquatch was a male.