A grizzly bear and a gray wolf faced off in Yellowstone National Park on September 4. The encounter looked like it had the makings of a classic battle royale after the wolf ran up to the big bruin and latched down on its rump. The bear, though, didn’t seem particularly fazed and mostly ignored the wolf. The wolf took two more bites on the bear’s butt and quickly retreated when the grizzly turned towards it. The grizzly finally sat down, effectively preventing the wolf from making another sneak attack. Retired ecologist Gary Gaston captured the interaction on camera and posted it to Facebook.

“We were watching wolves at Crystal Creek near Slough Creek at daybreak when this wolf decided to nip the bear,” wrote Gaston on Facebook. “Crazy wolves, these.” He suspected that the bear was defending an elk carcass. A good amount of carrion birds can be seen in the video watching the two big predators face off. According to Gaston, when the wolf walked away, so did the bear.

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Bears and Wolves Run Rampant in Yellowstone

The Greater Yellowstone Ecosystem (GYE) has one of the largest concentrations of gray wolves of anywhere in North America. There are over 500 wolves in the ecosystem and an estimated 94 wolves in the park alone as of January 2020. These wolves typically feed on elk, deer, and bison. Meanwhile, there are over 700 grizzly bears in the GYE. Grizzlies are massive and powerful beasts and can weigh up to 700 pounds in the Yellowstone area. They’re opportunistic feeders and will eat everything from pine nuts to cutthroat trout to elk calves. Fighting over food sources is one of the most common causes of animal-animal conflict in the wild.