“What he’s doing there is called wallowing,” says Craig Thoms, one arm slung over the steering wheel of his truck as we watch a bison roll around on the ground, hooves flailing, dust rising in small clouds. Watching this hulking creature behave like a dog in a grassy park makes me smile, though I resist the urge to whisper “Who’s a good boy?” as the bison rises and resumes his stroll alongside the rest of the herd.
Thoms cranks up the truck to shift our position and I raise my camera for the fifteenth time, unable to look away from these magnificent animals. The adults, dark and shaggy with big, expressive eyes, are unbothered by our presence. Even the calves, whose curly coats are a deep shade of orange, look on with a confident curiosity. Thoms is the bison manager at Wanuskewin Heritage Park, and the herd is well-acquainted with his booming voice and purposeful maneuvering.
Talking about his bison with the same gusto as a proud parent, Thoms tells me how the wallowing is just one example of their role as a keystone species. Bison twist around in the dirt to remove moisture from their triple-layered coats and enjoy a nice little scratch, alleviating the itchiness that comes with hair growth and shedding.
“When they shed, their coats come off almost like blankets,” Thoms says. “They scratch a lot of it off, and what you’ll see is birds carrying around bits of that hair and lining nests with it. I’ve actually seen rabbits with a chunk of bison coat in their mouths, presumably also lining their dens.”
Wallowing isn’t the only way bison help create habitats for other species — their natural grazing patterns facilitate biodiversity among local grasses and plants.
“Bison are travelers,” Thoms continues, gesturing to the land around us. “Research has found that bison used to travel between 14 to 16 kilometers [approximately 8.5 to 10 miles] a day. So they’d graze here, graze there, graze a little over there, which left enough grass for birds, insects, and other small animals.”
Beyond their innate tendency to wander, bison have discerning palates. The native grasses of the Prairies come into season at different times of year, so as one variety tastes sweet to the bison, another will taste bitter, and vice versa. Which, from an evolutionary perspective, makes perfect sense.
“If a plant stayed nutritious and palatable all the time throughout the year, there’s a chance that species would be eradicated,” Thoms says. He tells me about the vetch that grows here, which the bison find irresistible in the spring, but avoid in the summer when the plant turns bitter with developing seed pods. “But after the first frost hits, that vetch turns sweet and the bison go nuts over it.”
As the bison digest the vetch, seeds end up in their nutrient-rich manure piles, providing everything the seeds need to sprout and grow. And the presence of bison is helpful to plant life even when they’re not eating the grasses around them, because the simple act of walking around helps redistribute the seeds that catch in the hooves and coats of the roaming bovines.
Hundreds of thousands of bison used to traverse the prairies of modern-day Saskatoon, and they’d done so for thousands of years. The land comprising Wanuskewin is a valuable archeological site with evidence of more than 6,000 years of human history and includes an old bison jump — a steep dropoff over which hunters would drive bison — used by the Indigenous peoples of the Northern Plains. The nutritious meat and warm hides of bison were invaluable to the nomadic tribes, who deeply revered the animals and harvested no more than they needed for survival.
With colonization came the mass slaughter of thousands of bison, and today the most likely place to spot these animals around Saskatchewan is on commercial meat farms, crossbred for purposes of consumption rather than species preservation. The bison I’m admiring now, however — the herd of 26 that Thoms hopes to grow to between 50 and 75 — are genetically pure Yellowstone bison. This means that each is a direct descendant of the wild bison who managed to escape the widespread slaughtering efforts across the North American plains in the 1800s. In short, these animals are as closely related as possible to the bison that once ran wild across this very land.
By returning bison to these prairies, Thoms and the Wanuskewin team are better able to restore the land, gradually allowing the original flora and fauna to take hold once again. Thoms tells me they’re seeding 14 different species of grass in installments, utilizing the bison’s rotational grazing patterns to both nourish the herd and encourage healthy plant growth.
“We’re trying to bring conventionally farmed land back to native grasslands,” he says.
And the bison that have come home to Wanuskewin are certainly doing their part to help with this ambitious restoration project. They’ve even made remarkable archeological discoveries, uncovering 1,000-year-old petroglyphs and a rare carving tool with their wallowing activity.
It’s as though they were meant to be here all along.