Bison in the yellow hills of Lamar Valley, Yellowstone National Park, USA
1100 years ago, bison hunters abandoned a hunting ground they had long used. used for a long time. The animals did not disappear. The water disappeared — and hunters adapted to climate change.
More than a thousand years ago, bison hunters on the Great Plains of North America abandoned a small hunting ground despite the presence of bisonwhich continued to exist in sufficient quantity for their needs.
Yours abrupt departure there was no explanation. until a team of researchers dug deeper, and discovered that It wasn’t the scarcity of bison which took the hunters to other places.
Instead, they will have responded to droughts that lasted decadesand moved to places with a more reliable water supply and which presented characteristics more suited to an emerging and more coordinated way of hunting.
This pattern shows that the presence of bison alonewas not enough to keep the hunters in one place. On the contrary, climate variability favored specific locations and different forms of hunting that have not always been reversed when environmental conditions improved.
In the Great Plains of North America, bison have been hunted for thousands of years before populations collapse until almost extinction due to over-exploitation at the end of the 19th century.
But long before that, bison hunters used several strategies and different types of locations, sometimes alternating between them.
Now, researchers have sought to understand Why did the hunting stop? when bison ccontinued to be present at the Bergstrom sitein central Montana, where bison were hunted intermittently for about 700 years before the site fell into disuse.
The results were presented in an article published on Tuesday in the journal Frontiers in Conservation Science.
“We discovered that bison hunters stopped using a slaughter site in central Montana about 1,100 years ago,” he explains. John Wendtpaleoecologist and professor at New Mexico State University, in .
“It seems that hunters stopped using it because severe dry and recurring reduced available water to process the animals in a small nearby river. The abandonment of the site was a response to environmental stress factors and changing social and economic pressures”, he adds.
To understand what shaped the choice of hunting sites and organization, the team combined archaeological excavation, sediment collection and laboratory analysis.
“O Bergstrom site presented an enigma because it was used intermittently and abandoned when bison were common throughout the region and hunting was intense,” Wendt explained. “Why did the hunters leave to use a location that it had worked for so long?”
To get to the heart of the mystery, researchers excavated nine 1x1m pits in spring 2019. The excavated materials were documented and photographed, and charcoal fragments were sent for radiocarbon analysis. Two sediment samples were collected directly next to the excavation area.
The team analyzed them searching for pollen and charcoal fragments. They also monitored the presence of large herbivores and analyzed climate reconstructions. Based on this, the team was able to see if ecological changes explained Bergstrom’s abandonment, or if something else had kept the hunters away.
“The abandonment was not due to the site becoming ecologically unsuitable in any absolute sense. Bison were still presentthe vegetation had not changed and there was no substantial change in fire activities,” Wendt stressed. “Bison hunting was not simply tracking prey populations.”
Instead, severe droughts that lasted for decades reached the region before and after the final abandonment of the site. Such droughts limited the amount of water available, but also become less attractive for groups of hunters, places where water was not guaranteed.
At the same time, many hunters reorganizedmoving from small mobile groups that worked opportunistically to larger, more coordinated groups that used built infrastructure and occupied sites for longer periods of time.
“These larger operations were based on large slaughters and could produce surpluses for trade and winter storage, but they also meant greater dependence on specific resources such as waterfodder for larger herds and fuel for processing fires,” Wendt said.
The places that met these characteristics were scarceras they also needed topographical features suitable for large attacks by bison, such as cliffs for jumping and elements to contain the herds. If these characteristics were combined, however, these sites often saw repeated and large-scale use over centuries.
Favoring larger sites, however, meant greater dependence on everything going well, as these sites were more difficult to replace. The hunters worked in these places for generations and they could reorganize as conditions changed.
Maintain cultural knowledge and flexibility It’s most likely what allowed this type of hunting organization to persist through climate variability, the team said.
“Although people have adapted to the climate for much longer, the abandonment of Bergstrom shows that people have reorganized themselves in response to recurring droughts over the last 2000 years”, concluded Wendt.
