In a landscape known for its history of prodigious bison hunting, researchers have uncovered traces of a unique aspect of native hunting tradition — a camp dedicated to making the dried meat-and-fat product known as pemmican.

The camp is just part of a large bison-hunting site in north-central Montana called Kutoyis, which includes more than 3,500 stone features dating from to the 14th to 17th centuries, a heyday for bison hunting among the ancestors of the modern Blackfoot peoples.

The pemmican-making camp consists of at features used for processing the meat and fat taken from bison and turning them into a protein-rich and high-calorie food that was easy to carry and keep.

“This find is very important for adding to our understanding of pemmican production at Late Pre-Contact bison-kill sites in the region,” said Brandi Bethke who took part in the study.

“Before modern storage techniques like refrigeration, people had to come up with a way to store the products of their kill for both consumption and trade.

“A single bison may produce a few hundred pounds of meat, so a large kill site like Kutoyis would have produced thousands of pounds of meat at one time.”

It stands to reason that pemmican would have been produced at such a productive hunting site, Bethke added, because pemmican processing would have allowed the surplus meat obtained there to be preserved for years.

“It is … calorie-dense and easy to transport, which was a plus for highly mobile people such as the Blackfoot, whose ancestors hunted at Kutoyis,” Bethke said.

The camp was discovered in 2010, as part of The Kutoyis Archaeological Project, an ambitious effort to study the larger cultural landscape of Montana’s modern Blackfeet people.

“The Kutoyis Archaeological Project is the first systematic effort in the Northwestern Plains to uncover large-scale organization of prehistoric bison hunting,” said Dr. Maria Nieves Zedeño, an anthropologist at the University of Arizona who directed the study.

“The Kutoyis kill and processing sites were surveyed and excavated to complete a chronological profile of bison hunting in the region and to better understand intensive bison processing.”

A lot of archaeological research at bison-kill sites tends to focus on the jump, Bethke said, where bison were hazed off a cliff or into an arroyo and either fell to their deaths or were finished off by hunters.

But much of what happened after that, such as hide-tanning, meat drying, and making pemmican, is often overlooked.

“The reason pemmican production and other intensive bison processing activities are not always reported by archaeologists … has to do in part with the fact that they do not occur directly at the main jump site,” Bethke said.

“You typically find evidence of pemmican production adjacent to the main kill site, often on a floodplain, since many communal bison-kill sites occur near rivers and streams.”

And the special process of making pemmican tended to leave behind specific archaeological clues, she added.

“Traditionally, pemmican was made by first drying the bison meat in strips and then using two stones to pound it into tiny pieces,” she said.

“The dried meat would then be mixed with animal fat, which was … rendered by breaking up bison bones into small fragments, boiling them in water, and then skimming off the bone grease that floated to the top.

“So, if we are looking for evidence that pemmican was being made at a site, we’d be looking at the remains indicative of these activities — for example, boiling pits and associated fire cracked rocks, [and] bone that has been broken into many small pieces soon after the bison was killed.”

(See a massive bison-kill site recently discovered by archaeologists: “2,500-Year-Old Bison-Kill Site Offers New Clues Into Ancient Culture of Northern Plains“)

With this in mind, Zedeño, Bethke, and their colleagues used magnetometers to scan the floodplain near the bison-kill site at Kutoyis.

“Magnetometry uses special equipment to measure and map patterns of magnetism in the soil that are indicative of ancient activity, particularly burning,” Bethke said.

There they discovered dozens of so-called thermal features, where fires had been built, and excavated five fire pits that seemed to fit the pemmican-production profile.

“Once we located these buried thermal features, we dug test trenches to further explore them,” Bethke added.

At one spot, researchers turned up a wide boiling pit surrounded by a shallow berm, with stone chopping tools and fragments of bison bones scattered nearby.

At another, an assemblage of fire-cracked rocks, stone tools, and cracked bison bones appeared near a pit lined with sandstone.

A third included a ring of rocks with traces of ash.

The pits were the first cooking and boiling features ever found at Kutoyis, the researchers noted.

And in all, more than 20,000 fragments of bison bones were recovered.

“It was these findings that led us to interpret these areas as possible sites of pemmican production associated with the main kill site,” Bethke said.

(Read about another recent bison-kill find: “11,500-Year-Old Bison Butchering Site Discovered in Oklahoma“)

Radiocarbon analysis of more than two dozen of the bones yielded dates between 1410 and 1650 CE, indicating that much of the activity at the site took place shortly before contact with Europeans.

Together, these new finds shed light not just on the production of a well-known foodstuff of the Northern Plains, the researchers noted; it also provides new insights into how a key commodity — bison meat — came to be handled at a larger scale, with more specialized tasks, in the centuries leading up to European contact.

“The results of this study contribute to our understanding of not only butchery practices Late Prehistoric bison hunters engaged in at communal kill sites, but also the human and spatial organization involved in these pursuits,” the researchers write in their report.

“These findings are significant because they situate Kutoyis within a community of practice that was specialized regionally and symptomatic of large orchestrated hunts and subsequent processing activities.”

(Learn about a striking bison-hunting site recently revealed by fire: “Fire Reveals Human Stone Effigy, Bison-Kill Site in Montana“)

The researchers report their findings in the Journal of Archaeological Science: Reports.