Anyway.
Another theory about Mothman is that it was a pissed-off owl, mutant or otherwise. Barred owls are common to the TNT area, one might have gotten mutated to some giant proportion; fish there did. It's not entirely impossible that an
Incredible Hulk (Hawk?) of an owl was flapping around the place scaring the shit out of people.
Owls can get pretty terrifying when they feel threatened or when they're pissed off. I wouldn't want to be alone with one.
Exhibit A- Imagine this suddenly appearing before you on a dark road, with the eyes reflecting red.
Exhibit B- Owls can make themselves look considerably more evil when they want to.
I don't know that Mothman was an owl, but I guess I wouldn't be surprised. An owl would appear threatening and could divebomb people. An owl could have perched on the Silver Bridge. That place is all forest, I bet there are owls everywhere, and it's creepy enough in Point Pleasant that anything threatening would be way amplified.