The OL and I were going thru Yellowstone a couple of years ago and there was a bull in the middle of the road with his nose up a cow's rear. Did I mention this was a BIG buffalo? This dude was the leader of the pack for sure. Every time the car in front of us would try go pass by, the bull would turn on the car, snort, shake his head and stomp the asphalt. After about 10 minutes the cow had finally gotten off the road - with the bull still up her rear. That was about the scariest predicament I have been in except maybe for riding Skyline Drive on the Ultra.