It’s September, and many hunters have bull elk on their minds. Well, we recently came across this video from May 2022 that piqued our interest. It shows a natural predator taking down a young bull elk in excruciatingly slow motion. Be warned: The footage is pretty gruesome. It’s not for the faint-hearted. Wolves are not clean killers.

Wildlife photographer Evan Watts captured the stunning footage early in the morning of May 27, 2022, in Yellowstone National Park’s Hayden Valley, which is a popular area for wildlife sightings. Watts says the wolves that were hunting the elk were from the Wapiti Lake Wolf Pack. The video shows the wolves attacking the elk in a boggy area, slowly ripping chunks of flesh from it, before chasing it over a ridge, where they finished it off.

“I was in total shock when it happened,” Watts tells F&S. “I had spent days on end looking for wolves every morning and every evening before this, hoping to watch them make a kill. I couldn’t believe what an incredible feat of nature I was witnessing when it happened.”

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According to the National Park Service, the Greater Yellowstone Ecosystem is home to 30,000 to 40,000 elk and more than 500 wolves. Elk are the primary food source for the national park’s wolves, though researchers say bison are increasingly becoming an important food source for the canines. Wolves can eat up to 20 percent of their body weight in one sitting. They can reach weights of up to 110 pounds and hunt in packs that average around 10 individuals. On average, 18 to 22 elk are killed per wolf each year in Yellowstone.