Inside the South Dakota roundup of the country's largest bison herd

CUSTER, S. D. -- The earth rumbles as 1,100 buffalo stampede across the South Dakota prairie. About 60 volunteer cowboys and cowgirls ride herd, including 81-year-old Bob Lantis.

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Bob Lantis

Jake Barlow/CBS News

The spur-jingling, pistol-toting, chaps-wearing buckaroo has participated in the nation’s biggest buffalo round-up of its kind for the past 45 years.

Lantis says the best part of the roundup is the run.

“When we’re actually pushing the buffalo and they’re running just as hard as they can run, we’re running just as hard as we can run. It’s an adrenaline-kicking son of a gun, I’ll tell you that for a fact,” he said.

A lot of fun, yes, but a buffalo can weigh 2,000 pounds, and some of them have an attitude. Just ask first timer Chris Richgels.

“I had a bull turn and come at me and my horse we had to boogie out of there pretty quick,” Richgels said. “It made for a memorable event.”

More than 30 million buffalo once roamed the U.S., but in the 1800s they were slaughtered by pioneers, almost to extinction.

Today, one of the country’s largest wild herds calls Custer State Park home. The 1934 round-up is believed to be the first caught on film, and they’ve been held every year since 1965.

There is a purpose to the whole spectacle, according to Lantis.

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A buffalo takes a break

Jake Barlow/CBS News

“Health of the herd, to hold the herd in a manageable number so that they don’t over-graze the land,” he said.

After the roundup, they’re vaccinated, calves are branded and some cows are sold.

For Lantis, it never gets old.

“When you quit doing that thing that you like to do, you’re gonna die. That’s my thought. I ain’t gonna quit. I’m gonna keep on riding,” he said.

  • Chip Reid

    Chip Reid is CBS News' national correspondent.