Custer, S.D.

Buffalo rumble when they run. Dust plumes follow the herd, the animals at the back like dark phantoms plowing through fog. With shaggy beards and thick shawls of front-shoulder fur, they run together with a rolling motion, thundering down the valley as cowboys drive them toward corrals.

South Dakota’s roundup of bison—buffalo,...

The Custer State Park buffalo roundup in Custer, S.D.

Photo: Custer State Park

Custer, S.D.

Buffalo rumble when they run. Dust plumes follow the herd, the animals at the back like dark phantoms plowing through fog. With shaggy beards and thick shawls of front-shoulder fur, they run together with a rolling motion, thundering down the valley as cowboys drive them toward corrals.

South Dakota’s roundup of bison—buffalo, as Dakotans call them, ignoring zoology—has been an annual ritual in Custer State Park since 1965 (and intermittently earlier, after the animals were introduced to the 71,000-acre park in 1914). The purpose of the roundup is to get a rough count, give medications, and separate out some to be sold, so the park can maintain a sustainable number.

This year’s roundup, on Sept. 24, corralled roughly 1,400 buffalo before an audience of 22,452 people. What started as a simple cattle drive has turned into a major show, the last tourist event of the summer season. “I would say I have the easy job,” says Chad Kremer, manager of the park’s herd. The hard job these days is herding the crowd that comes to watch, “getting people in and parked efficiently so that we can get started.”

Cars covered the small hills like sprinkles on scoops of ice cream. Mothers poured coffee from thermoses in the cool morning of a hot day, while the crowd sat on brightly colored blankets, waiting to see the show. Children wore ill-fitting cowboy boots and hats, strings dangling beneath their chins. There wasn’t a mask in sight.

Jeremy Revis, a train conductor from Sterling, Colo., suggested that he and others came in part because they wouldn’t have to wear masks. Others came just to see the buffalo. Dusty Baker, a rancher from Sulfur, Okla., who hosts a YouTube channel about his own bison herd, explained: “It’s a sight you don’t really get to see in America that often. It’s the Wild West out here.”

They traveled from all over: New York, Montana, California, Missouri, Minnesota, Pennsylvania. When the roundup was done, the tourists poured like water down the hills to wash up against the fences, gawking at the buffalo in their corrals.

The actual rounding up was done by some 60 riders on horseback, divided into three groups. The first was the lottery winners, 20 chosen randomly from hundreds of applicants. Then there were the friends, family and political associates of Gov. Kristi Noem. And finally there were the actual working riders, what Mr. Kremer calls his “core group”—park rangers and ranchers who return year after year. The roundup “needs some seasoned hands and people that know livestock and buffalo to do the prep work so that we can put on a show like this,” said Lt. Gov. Larry Rhoden. “The real work is done in the weeks before and the weeks after.”

Most of the lottery winners came from out of state, and it showed. One husband-and-wife team wore matching silk bandanas, carefully tied. A woman from California showed up in black knee-high boots and an English riding-style helmet—matched, in homage to the occasion, with a bedazzled cowboy belt and fringed chaps. Her horse lifted its legs in a gait better fitted to a dressage test than a Western roundup.

The dignitary riders seemed more authentic, although their gear looked new. The real work was done by the core group, mostly men in faded jeans, Western shirts and well-worn hats.

They have been doing this kind of work for a long time, and they sank onto their horses in a way possible only for those who have been on horseback their entire lives. Owen Garnos, 81, a rancher from Presho, S.D., has ridden among the roundup’s core riders each of the past 20 years. “I do it to see my friends,” he said.

“We’ve been here in frost, hard freeze and sunshine,” said Steve Olivier, a rider from St. Cloud, Minn. “I’ve been out 32 years in a row.”

For some people, horseback riding is a sport: the show jumpers with their wrapped legs and the riders in black jackets, jodhpurs and polished boots. For others, it’s a display: politicians and rodeo queens waving their cowboy hats at the crowd in a Western-state parade. Riding is even a tourist industry: novice riders from the city perched on slow, placid mares for a trail ride.

But horseback riding can also be work: people on horses moving cattle, riding fence lines, and pulling equipment. Quiet, competent people with calm eyes, agile bodies, and weathered hands and faces. They are still around. There are still cowboys out on the South Dakota meadows and hills, the people who get things done.

Ms. Bottum is the Joseph Rago Memorial Fellow at the Journal.

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