Home » Grass-fed Bison Returns to South Dakota Prairie

Grass-fed Bison Returns to South Dakota Prairie

A bison stands alone in a grassy meadow in North Dakota’s Theodore Roosevelt National Park. Getty Images.

By Jill Henderson

Another spring day begins on the Great Plains of northwestern South Dakota. The short-grass prairie at 777 Bison Ranch bristles with colorful wildflowers and native grasses. From the view of a drone flying high above, the bulky mass of 1,600 American bison stream like a watercourse across the ridges and shallow valleys as they move towards fresh grazing grounds. Seeing so many bison together in one place is not only breathtaking but an incredibly rare opportunity for most people. For a brief moment, it is easy to forget the long and uncertain history of these icons of the American West and to lose oneself in the beauty of the renaturalized prairie on which they and their plant and animal allies once again thrive. For Mimi Hillenbrand, owner and manager of the 777 Bison Ranch, this amazing landscape has been forged in a labor of love for bison and the Northern Plains from which they originated.


American Bison

Before the arrival of Europeans, more than 60 million American bison roamed the prairies and plains of North America. From the Alaskan wilderness to the rich grasslands of northern Mexico, and from the Appalachian Mountains to the Great Basin of Nevada, the annual migration of bison across the continent in massive herds not only shaped the richly diverse grasslands upon which they thrived but were also an integral part of the culture and survival of indigenous peoples of North America for hundreds of thousands of years.

As Europeans made their way into the interior of the continent they too found the bison useful. Everywhere they went, bison were killed by the thousands to fill a growing demand for leather and fur back east and across the Atlantic.

Between 1871 and 1889, in an inexcusable act of terrorism, bison were ruthlessly slaughtered and at times left to rot for the sole purpose of demoralizing and denying Native Americans one of their most sacred spiritual icons and their primary source of food, clothing, tools and shelter. Without the bison, the western tribes were defeated and relocated to make way for western expansion.

In 1883, a young Teddy Roosevelt traveled to the Dakotas to hunt the last of the largest mammals on the continent. He stalked a lone buffalo bull for the better part of a week and then danced around the carcass in celebration. Later he would lament the condition and demise of the once-mighty bison and rally fellow conservationists to the cause of their preservation. By the early 1900s, roughly 1,000 American bison were left alive on the continent, most of which had been corralled into confinement. A mere twenty-three lived free in the protective central valley of Yellowstone National Park. It is from these surviving remnants that all genetically pure American bison alive today originate.

A Bison Ranch is Born

In 1972, Ray Hillenbrand and his brothers purchased the 777 Ranch located in a remote area southeast of Rapid City. The family lived in Batesville, Indiana, where Ray managed his family’s businesses. The ranch was stocked with beef cattle and the land was worse for wear. After nine years of spending summers at the ranch, the Hillenbrand family permanently relocated there in 1980.

From the very beginning, conservation was at the heart of what the Hillenbrand family wanted for their growing ranch and in 1983, Ray introduced the first 100 head of bison. Mimi, then in high school, recalls the moment they decided they were done with beef cattle.

“It was a really bad winter and early spring and the cattle were calving right in the middle of a blizzard. It was a lot of work getting them into the barn and keeping them warm and all that mess. And as soon as the blizzard was over and the sun came out, all the bison calved and we reevaluated everything,” she said. “We made the switch entirely to bison in 1984-85 because part of our farm goal was to bring back the prairie. And since the bison evolved here and utilized the land in the right way and had great instincts, why not use them to help us?”

“About the same time we decided to go all-in on the bison in the late ’80s,” she continued, “Allan Savory was going around and talking to different ranching communities in the area. I can still remember sitting in a freezing barn listening to Allan speak and thinking, ‘Oh my gosh, that makes so much sense!’ That was 30 years ago and we’ve been using holistic grazing ever since.”

Better All the Time

From the very beginning, Mimi loved being on the ranch and working with the bison and after high school, she earned a bachelor’s in wildlife biology with an emphasis on range management from the University of Montana. She followed that up with a master’s degree in agricultural sciences from Colorado State University. She returned to the ranch and worked alongside her father for several years before he handed the reins over to Mimi in 2004. “I’m living my dream from childhood, doing conservation work and making a living out of it,” she said.

The 777 Bison Ranch is comprised of 26,000 acres broken into 26 pastures. Because the bison are not given any supplemental feed of any kind, the ranch’s annual grazing plan must take into account not just the growing season, but the dormant season as well. “We plan for plant recovery and our recovery time ranges from 60 days, which is our minimum, to 120 days, depending on the weather,” said Mimi. “We’re moving the bison every two days to three weeks depending on pasture size and how the grass is growing.”

Because South Dakota is a semi-arid prairie that receives only 14 inches of precipitation annually, most of which comes in the winter and spring, keeping the size of their bison herd in proportion is crucial to what Mimi calls their “caring capacity.” In 2020, the ranch was stocked with 1,800 head of bison, but because of the recent drought, she and her management team decided to take that number down to 1,650. “The way most people stock out here is 23-25 acres per animal unit, but the way we’ve been managing our land, we’re down to 18 acres per animal unit, so we’ve increased our production substantially over the years,” she said.

Healthy Soil, Healthy Planet

A large part of any conservation-minded land management includes introducing or encouraging a wide array of native and naturalized plants for livestock as well as wild animals, birds and insects. For Mimi, having a good array of native plants and useful forage is a top priority. “There’s nothing especially wrong with introduced species. They were introduced because they are good protein for livestock. But as much as I don’t want them, they serve a purpose and they are still converting sunlight and that’s good. But just by the way we’ve been managing we have increased our diversity by 3-4 times.”

Non-native plants on the ranch include Kentucky Bluegrass, Smooth Brome, Cheatgrass, and Crested Wheat.

“One of our big successes is on some of the pastures that had been planted with Crested Wheat,” she said. “Just the way we’ve been grazing them has knocked that back and allowed Green Needle Grass, Western Wheat, and sods like Buffalo Grass and Blue Gramma to emerge. Even Big Bluestem makes its appearance when moisture is just right. But it’s like ‘Hey, now we’re really doing it!’”

Mimi explains that their desire for diversity, soil building and sequestering carbon is what got her to bring in Applied Ecological Services to do a year-long study to see if what they were doing with holistic management was actually achieving those goals.

“In some places, we’ve built inches of topsoil over the 30 years we’ve been doing HM,” she said. “And compared to some of the traditional grazers, our diversity is three times better and our water infiltration is off the map. Some of the springs that used to be seasonal now run year-round. It’s really super-cool.”

Mimi says that HM works, but it takes time.

“You’re not going to see these kinds of results in the first five years,” she said. “Our success is something that’s been going on since we made the switch to bison. When we were running cows in the ’70s and ’80s, we were doing traditional grazing and our soils were tied up in blue gramma and buffalo grass. Of course there is nothing wrong with those as good forage, but they can choke out other native species. We’re just working with it and now we have a really great mix of species. Back in the ’80s, we needed more cool-season plants and now we need more warm-season plants. It’s kinda cool to watch how everything just works itself out.”

Diversity is Key

Diversity is not only good for the environment and wildlife like dung beetles, birds, prairie dogs, and even coyotes — it’s good for bison, too. Because all pure American bison today originated from those remnant herds of the 1900s, Mimi is determined to have the most genetically diverse pure-bred American bison herd anywhere in the world and keeps track of her progress with genetic testing. “There were only 1,000 head of bison at the turn of the century and now we’re almost to half a million, which is a wonderful success story for this animal,” she explains.

“There are all these satellite herds like Wind Cave, Badlands, the Buffalo Range of Montana, Elk Island, Yellowstone, and Teddy Roosevelt (all of which are state and national parks) that have what I call ‘heritage genetics’ and that’s what I want in my herd,” she said. “I started with bison from Elk Island and Cap Rock Canyons State Park in Texas, which was the original Goodnight herd from 1878. I don’t like a closed herd and bison don’t usually inbreed, so I’ve been acquiring animals from all these really cool places.”

Handle With Care

Among the various aspects of running a grassfed holistic management operation, attaining certifications to prove to buyers and consumers that you are doing a good job can be the icing on an already sweet cake.

“I think consumers want to know where their food comes from and how the animals are treated, Mimi said. “And I can tell you where each one of our animals has been from conception to the moment it left the ranch. I can tell you what that bison was eating and where it was eating it and I can give you his whole life history and what pasture he was in on a certain day and I think that’s pretty cool.”

In addition to partnering with organizations dedicated to education on the nuances of raising of bison and the benefits and implementation of holistic and regenerative practices, the 777 Bison Ranch is a Savory Partner and is Land to Market Certified through the Savory Ecological Outcome Verification (E.O.V.) program, which helps connect regenerative producers with buyers. The ranch is also an American Grassfed Association (AGA) Certified Producer, which guarantees that their bison are always raised on pasture with no confinement and never treated with hormones or antibiotics. The Triple 7 was also awarded the Audubon Certified label, which is awarded for meat that is sustainably raised in a way that benefits wildlife habitat, particularly for native bird species.

In addition to these prestigious certifications, 777 was the very first bison ranch in the nation to receive the Global Animal Partnership (GAP) certification. They did this, in part, by having Dr. Temple Grandin come to the ranch and help design safe, animal-friendly handling facilities specifically for their herd. Mimi also took classes from the late Bud Williams, who was famous for teaching ranchers how to train their cattle to stay together and move as a natural herd, which helps reduce stress during rotational grazing moves. “I took several classes from Bud and even went to Canada to learn from him. We still practice his techniques every day and I think our round-ups are truly amazing because of it.”

Another of Mimi’s passions is teaching, coaching and encouraging others to learn more about raising bison, implementing holistic management practices, and increasing biodiversity on their farms and ranches. In 2019, the 777 was presented with the Area IV Excellence in Range Management Award from the South Dakota Section of the Society for Range Management. In addition to the Triple 7 being featured in the films Dances With Wolves and Wyatt Earp, it also made it into the 2019 South Dakota Grassland Coalition Planner and video series, Voices for Soil Health, which was produced by the USDA NRCS South Dakota to promote healthy soils, grasslands and ecosystems.

Mimi is also board member of several prestigious organizations working for the promotion and preservation of the American Bison, including the National Buffalo Foundation and the National Buffalo Association, where she works on the science and research committee and the conservation committee. She is also a board member of South Dakota State University’s Center of Excellence for Bison Studies.

Women in Eco-Ag

When asked what it has been like to be a woman in charge a 26,000-acre bison ranch in what is inarguably a field dominated by men, Mimi laughed and said, “I get asked this all the time and I know a lot of people want me to say it was so hard being a woman and this and that, but I never let that bother me because I’m doing what I want to do. I’m a very fortunate person and I’m living my dream and my passion and nobody is going to stop you if you believe in what you do.”

“My biggest challenge was finding the right team, the right people who embraced my passion and vision for the ranch. I’ve worked with my ranch manager, Moritz Espy, for a long time now, but when he first came on he thought I was some tree-hugging hippy chick with all these crazy ideas. It took him a few years before he got what I was doing, but Justin Selke and Cody Smith, the other two gentlemen on my team, got it right away. But we’re all on the same page now and we joke about it all the time,” she said.

“I would say to any woman who has a dream to ranch or farm to remember that everybody has challenges, male and female. But if you feel it in your heart and soul, if it’s your dream and your passion, you can accomplish anything and nobody can stop you.”