Fall is practically upon us, and that means the rut isn’t far off. For most of America’s big-game species, this means males fighting over females in sometimes brutal battles. And no animals fight quite like bighorn sheep do. Earlier this week, Colorado Parks and Wildlife’s Jerry Neal captured footage of an epic brawl between several Rocky Mountain bighorn sheep rams. The agency posted the video on Facebook, noting that “wildlife is wild”—something you’d think no one should need to be alerted to, except that year after year some people try to get too close to rutting big game with their cameras.

Bighorn sheep tend to live in relatively large herds. Each fall, the rams fight to establish dominance to determine mating access with ewes. Rams can charge into each other at speeds up to 40 mph in battles that can last several hours before one ram submits. True to the species’ name, a bighorn ram’s horns can weigh up to 30 pounds, which is equivalent to the mass of all the rest of the bones in a male’s body.

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“Observe animals from a safe distance—safe for you and safe for the animals,” added CPW in the Facebook post. “You can get a close-up view by using binoculars, a spotting scope, or a camera with a telephoto lens.”

Rocky Mountain bighorn sheep were once on the verge of extirpation in Colorado. The state’s population had dwindled precipitously by the early 1900s because of diseases introduced through European livestock and unregulated hunting. CPW reintroduced bighorn sheep in the 1940s, and the species’ subsequent recovery is a testament to the North American Model of Wildlife Conservation​​. Today, over 7,000 sheep live in Colorado, and a small number of lucky hunters draw highly sought-after tags to hunt them each year.