“Secret” revealed
It turns out it’s just a ‘plain old’ dog named Doug. He’s a rescue dog from Valdez, Alaska. And just like a sasquatch, a celebrity, or any other weird-looking creature caught on film, he enjoys privacy and being seen as rarely as possible. And so, like a mythical monster, Doug hides in obscurity, never to be seen again by the hungry curious eyes of twitterers, remaining a legend.