Bison Death Plunge
‘Amazing’ archeological discovery at Caprock Canyons
reveals a place where Native Americans drove bison off a cliff.
IN 2021, Rick Day and his wife, Susan Day, had a particularly rowdy group of students in their science classes at Lockney Junior High School. It wasn’t that the students weren’t interested in learning. It was more that they had an excess of energy — something the Days understood from their years of teaching. Rick, a Texas Archeological Steward in his spare time, had an idea.
“We wanted to take them on a geologic tour,” he says.
And so, on a November day in 2021, it was the pursuit of the perfect tour route for their students that led the Days out into the wilderness of Caprock Canyons State Park east of Lubbock. They trekked down a park trail for less than a mile, then departed from the path (with prior approval from the park) into the brush.
For another half a mile, the Days followed the gentle curve of the canyon, trekking across red dirt interrupted by bubbles of crystalline gypsum and rafts of scrubby vegetation. Spotting an interesting rock, they scrambled up onto a ledge at the foot of a cliff.
That’s when Rick saw the bones. Jutting out of the cliff side, painted red by the iron-rich sediment beneath the Caprock, hundreds or maybe thousands of bones formed a layer in the stratigraphy.
Rick had been exploring this country since he was a child, and after spending 15 years as a steward for the Texas Historical Commission, he knew quite a bit about the cultural history of the place.
“I looked at the cliff and I saw the way the bone was oriented,” he says. “When I saw it, it seemed to me that if this is not a jump, then I don't know what a jump is.”
A jump — short for a bison jump — is a landform used by native people to harvest bison by driving a herd of the animals off a cliff. The ideal bison jump has a smooth uphill leading to a surprise dropoff. Once the bison noticed the edge, it was too late; the momentum of the herd pushed them off the precipice.
The bison would fall to their deaths, and people would set up camps at the base to butcher the animals and preserve the meat. The various parts of the bison had many uses; hunters would tan the hide, cook the meat immediately or cure it for future use, and even eat curdled milk in the stomach of baby bison, possibly prized as a cheese-like delicacy.
The only other known bison jump site in Texas, Bonfire Shelter, is located in a privately owned stretch of rugged gorge near Langtry, along the Rio Grande. It’s the oldest and southernmost jump site in North America.
Other notable examples of bison jumps include the dramatic Head-Smashed-In Site in Alberta, Canada, Vore Buffalo Jump in Wyoming and First Peoples Buffalo Jump in Montana. Bison jumps became obsolete with the advent of horses and modern weapons. The most recent jump sites in North America were active in the 1800s.
“These collective drives of bison as a way of hunting are a really dramatic thing that lingers really prevalently in the psyche of Plains Native Americans hunting,” says Gus Costa, an archeologist who’s working on the newly discovered site. “[Bison drives often] were an annual event where people were getting together, hunting bison, having a feast and doing lots of interesting social things.”
To determine if the site Day had discovered was indeed a bison jump and not some other type of kill site, Texas Parks and Wildlife Department (TPWD) archeologists, scientists and students spent months painstakingly collecting and documenting bones and fragments of stone tools.
The site’s positioning at the foot of a cliff, plus the fractures and positions of the bones, confirmed that the site, nicknamed the Nighthawk site after the black-eyed, desert-dwelling birds that nest nearby, is a bison jump, the first discovered in Texas in 63 years.
“The fact that we found this site is pretty incredible,” says Tamra Walter, an associate professor of archeology at Texas Tech University. “It’s a once-in-a-lifetime kind of site. It’s so incredibly rare.”
The site is also incredibly fragile. With the wind and rains of each passing year, more bones — and more information about the site — wash away into the red creek beds of the canyon. TPWD cultural resources staff are actively monitoring the site and will utilize the data collected here to plan for future management of this and other archeological sites in the park.
Costa, who is currently analyzing data from the Nighthawk site, is devoted to capturing the information available before it’s too late. “The main thing is, this is rare, it should be preserved for the benefit of the public, and it’s disappearing,” he says.
IN JUST A FEW short months since the Days found it, a team of scientists and stewards from TPWD, Texas Tech and elsewhere assembled around the Nighthawk site. In collaboration with TPWD, Texas Tech archeology professor Brett Houk and Walters created a field school, allowing Texas Tech students the chance to experience a dig and help with the analysis.
“The field school was really beneficial for us and for the students at Texas Tech,” says TPWD’s cultural resources coordinator Tony Lyle.
On a November weekend in 2022, our photographer Maegan Lanham and I tag along as they’re wrapping up excavations for the semester.
On Saturday we are up at the crack of dawn, bundled up against the North Texas winter chill. Students appear one by one from the park building in which they had laid their sleeping bags on the floor (with nightly temperatures dropping into the low 20s, it was too cold to camp).
We arrive at the site around 8, and everyone splits off to various excavations. Some are positioned because of the amount of bone there, while others are “salvage units” in the areas deemed by scientists to be at the highest risk of being eroded away.
Students, professors and volunteers are hard at work on all of them. As soon as a bone is uncovered, the researchers spray it with copious amounts of a protective orange foam, which lends each bone the appearance of a huge, irregular Cheeto.
Over the first few months of the excavation, the researchers found plenty of bones, but no artifacts, which led some to speculate about whether humans were involved at all. But this didn’t sit right with Houk.
“Bison aren’t going to normally just walk off cliffs,” he says. “They’re smarter than that.”
The speculations were laid to rest later in the excavation when one of the students found a chert flake — evidence of human presence at the kill site. Bones unearthed later showed cut marks, further evidence that people were harvesting meat from the fallen animals.
Carbon dating places the bones in two major jump events taking place in 319 and 1379 AD. Many Southern Plains tribes have passed through the area, so it’s not clear which groups might have used the site. The site lies on lands used by people whose descendants form the Kiowa, Comanche and Lipan Apache tribes as well as other groups.
“It’s pretty amazing and significant when you think about the continuous history of the buffalo nation of the Southern Plains being in this area of Caprock Canyons for thousands of years,” says Lucille Contreras, CEO and leader of the Texas Tribal Buffalo Project and a member of the Lipan Apache tribe.
JUMP SITE OR KILL SITE
AFTER ESTABLISHING THAT people were indeed harvesting the meat of the bison, researchers were next faced with the task of determining whether the Nighthawk site was a jump site or a different kind of bison kill site.
Native Americans had many ways of killing bison, including hunting with spears or arrows, or with “arroyo traps,” in which hunters would drive the animals into a narrow creek where they would get stuck and trample each other.
In fact, just miles from the Nighthawk site is the Lake Theo Folsom Bison Kill Site, where hunters drove a now extinct species of bison into a canyon and slaughtered them using spears. The site is older than Nighthawk, dating back 10,000 years.
Once the researchers collected bones and artifacts from the Nighthawk site, they had to work out how the bison were killed. By studying the breakage patterns in the bones, Costa was able to document compression fractures that indicated a fall from a great height.
“It was about a 20-meter fall from the top [of the cliff] to the surface when the bones accumulated,” Costa says. “That’s about six stories… This jump is one of the highest jumps that I know of.”
Finding a new jump is exciting for a number of reasons. “It adds critical data to the story of late Holocene bison hunting in the Southern Plains,”
Plus, the hundreds of bones retrieved from the site will give biologists an opportunity to study Southern Plains bison through time. At Caprock Canyons, where the Texas State Bison Herd still roams, the remains of these more than 1,000-year-old bison could tell a story of how the species has changed and how it has remained the same.
“It’s kind of like being able to do paleontology at Jurassic Park, and then go and look at the dinosaurs,” Costa says. “We have those living examples … There are potentially exciting opportunities [at Caprock] to look at bison in the present and the past, through time, all around the park.”
The site looks much different now than it did when the bison fell to their deaths. In the ensuing years, the cliff has receded dramatically. According to Costa’s models, about 70 percent of the site is now eroded away. In the coming years, the cliff will retreat even more.
“We’re just finding the bare remnants of what used to be here,” Houk says.
Preserving history in the face of such rapid environmental change poses a conundrum. Excavating is expensive and time-consuming, and often does irreparable damage to the site.
“For us to take it all now and put it in a museum somewhere, that’s cool for everybody now, but we lose part of that story when we do that,” Park Superintendent Donald Beard says.
Because of the environmental conditions at the Nighthawk site, however, time is of the essence.
Over the next few years, TPWD archeologists will continue to collaborate with researchers to wrap up excavations. They plan to recover all artifacts and bison bones in order to fully analyze this important archeological site. In the meantime, they’ve avoided giving precise location information to discourage looters and vandalism.
The Panhandle-Plains Historical Museum in Canyon features the dig in its exhibit, "The Fall and Rise of an American Icon," which will run through September of next year. Caprock Canyons, which already has interpretive materials about the Lake Theo site and bison hunting in general, will add a new exhibit about the Nighthawk site.
“Chasing buffalo off of the buffalo jump site so that we could harvest the meat, harvest the hides, utilize the bones, is directly related to a way of life that thrived in the area and is no longer thriving,” says Contreras, the tribal buffalo leader. “What an amazing, amazing gift that those hikers received when they found [the site] and realized what it was; and what an amazing gift of this site for the people to continue learning about this buffalo way of life and all the impacts of the past and the present and the future.”
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