This clip was originally captured by a user who watched the live webcam at Yellowstone accessible at: http://www.nps.gov/features/yell/webcam/oldFaithfulStreaming.html
In this clip we see what looks like four Bigfoot creatures stalking four buffalo in Yellowstone National Park. As the clip is unaltered and captured from the official webcam we can rule out photoshop or any other type of hoax being at play here.
What do you think this is? Comment below.