THE CALM OF THE WILD

WENDING THROUGH THE WATERS, WHISPERING OVER THE PEAKS-NATURAL RHYTHMS SOOTHE IN THE BLACK HILLS OF SOUTH DAKOTA.

- MARY BEAUMONT

PRAIRIE It is the quiet before the thunder. Morning sun has further gilded the golden grasslands of Custer State Park, spread over more than 70,000 acres in western South Dakota. Cowboys and cowgirls mill on their mounts, dotting ridge lines above a sprawling valley. Riders chat; horses whinny. Most eyes fix on the sight below-hundreds of cocoa-hued bison, grunting, wandering and waiting.

Then, a hoot. A whipcrack. More shouts. Riders begin to move in an annual choreography to gather the herd from the open range, check its health and chart its future.

The annual Custer State Park Buffalo Roundup and Arts Festival attracts more than 20,000 spectators, who edge the vistas the last Friday of each September to watch riders corral the beasts. But this isn't herding cattle. (And, if we're getting technical, they aren't buffalo.) The bison is North America's largest mammal. Bulls can weigh up to a ton and reach 6 feet tall. And they can move, running 35 mph with the ability to turn on a dime.

Around 1,300 head of bison call the park home. But they don't just live here. They are the lifeblood, the heartbeat of this place. Once 30 million strong and the cornerstone of life for Native Americans, who used them for food, fuel, shelter and spiritual celebration, bison were driven to the brink of extinction by settlers.

Custer bison descend from the private herd of a South Dakota rancher named James "Scotty" Philip, whose wife was part Cheyenne. Philip and his family worked at the turn of the 20th century to rescue the dwindling species and eventually sold a few dozen animals to the state of South Dakota.