Watch as two of nature's heavyweights cross paths in one of the wildest places on Earth.
Alaska's Katmai National Park is a region teeming with big bears and big moose. The moose usually don't interfere with the bears and vise versa, unless its the rut, when bulls seek out their mating partners.
During the rut, bulls become fearless. Their testosterone levels reach supercharged levels, and they do things they normally wouldn't do.
This footage from naturalist Brad Joseph shows a trophy bull getting a little too close to a group of grizzlies on his way to find new mating partners.
Bears rarely attack moose, but you can tell these grizzlies don't want this bull sauntering through their territory.
From a hunter's standpoint, the trophy bull is amazing. He has an incredible flat antler rack and a massive body. The bears are nothing to sneeze at, either.