This is the extraordinary moment a grizzly bear charged at a huge herd of elk.

Grizzly bears usually eat nuts, roots, fish, and small mammals such as squirrels, so witnessing a bear hunt such a large creature is unusual, especially in such high quantity and in such an open space.

Wildlife photographer Deby Dixon captured this footage while observing a large herd of elk gathering and grazing at the foot of Hayden Valley in Yellowstone National Park, Wyoming.

Dixon described the sighting: “In the Hayden Valley area of Yellowstone National Park, a grizzly bear chased a herd of elk relentlessly. On this day, the elk managed to escape. At this time of year, when elk calves are being born, the grizzly stay busy hunting, trying to find the elk calves hidden in the sagebrush. For the most part, grizzlies are opportunists and often steal carcasses from the wolves so it is not often that we see one chase a whole herd of elk.”

The bear was not able to get close enough to make an attack in the video above. But in the clip from our archives below, we can see what happens when a grizzly does manage to close in…

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