It might be time to rethink about how we view FLIR thermal imaging of potential Bigfoot in the field.
Men (hand on the left) have less constrictive vessels than females, hence their hands can be warmer than a female's. As well, their musculature involves the vessels to support those muscles, hence they may show up on a FLIR thermal imager a bit differently than a female.
Now, let's expound this concept to musculature of a Bigfoot versus a human. If you have a being who is vastly more muscular, exercises, athletic, and powerful, imagine the vascular system and heat signature they would give off.
We might need to rethink how we determine a Bigfoot on thermal imaging versus a human and this could help us to better explain if we are dealing with them or us, male or female.