Bison (also known as buffalo) are one of Yellowstone's success stories. After nearly dying out they are to be found in quite high numbers.
They seem to be wonderfully stoic creatures.
This one wasn't even upset by 'Old Faithful' erupting...
...nor was her baby!
Bison babies are VERY cute.
Traffic in the park is often disrupted by 'bison jams'. They are more than happy to block the traffic.