The Story of Bison Hunters Who Moved Because of Drought

For nearly 700 years, a site known as Bergstrom in central Montana served as a place for hunting and processing bison for Indigenous hunting communities of the North American Great Plains. The site was used repeatedly over a long span of time, indicating that it was not merely a stopover point, but an important part of their subsistence system. However, around 1,100 years ago, the location was abandoned and never used again. Interestingly, the decision was not driven by the disappearance of bison or by ecosystem collapse. The animals remained available and the vegetation was relatively stable. So what changed?

Research published in the journal Frontiers in Conservation Science on February 10, 2026 suggests that the key factor was likely recurring, decade-scale drought that affected water availability around the site. The Bergstrom site lies near a small tributary that for centuries supported bison-processing activities. Water there was not merely for drinking, but a vital element for cleaning, skinning, and processing large animals in significant numbers. When prolonged drought patterns made the water flow unstable, the site’s practical function weakened.

“We found that hunters stopped using this site about 1,100 years ago,” said Dr. John Wendt, a paleoecologist at New Mexico State University and lead author of the study. He explained that repeated severe droughts likely reduced water availability in the small stream near the site, which was crucial for processing game animals. “This abandonment appears to have been a response to environmental stress as well as social and economic changes,” he said.

Not Because the Bison Disappeared

The research team did not rely solely on archaeological artifacts. They used radiocarbon dating, pollen and charcoal analysis to reconstruct past vegetation and fire conditions, as well as paleoclimate data to understand regional drought patterns over the past several thousand years. The results show that bison populations remained present in the area and that there were no major vegetation shifts that could explain the site’s abandonment. In other words, Bergstrom was not deserted because of prey scarcity or drastic ecosystem degradation.

These findings challenge the simple assumption that hunting communities always moved solely in response to animal migrations. In this case, logistical factors and resource stability proved more decisive than the mere presence of prey.

The research also points to changes in hunting organization during that period. Hunting practices in the Great Plains began shifting from relatively small, mobile groups to larger, more coordinated communal operations. Mass-hunting systems enabled large-scale kills and the production of surplus for winter storage and possible intergroup exchange. However, this larger and more complex model came with consequences, including a greater need for stable resources, especially water and fuel for processing.

“These larger operations produced surpluses for trade and winter storage,” Wendt explained. “But they also meant greater dependence on specific resources such as water, forage, and fuel for processing fires.”

In this context, sites like Bergstrom—hydrologically marginal—became less ideal. Recurring drought made the nearby stream no longer reliable enough to support increasingly large-scale operations.

Never Returned

One significant finding is that the site was never reused, even after climatic conditions improved. This suggests that the decision to abandon Bergstrom was not merely a temporary response to a single drought episode, but part of a broader social reorganization. Once large-scale communal hunting became the norm and more stable locations were chosen, the old site permanently lost its relevance.

The study shows that human adaptation to environmental change does not always take the form of large-scale migration or dramatic collapse. Sometimes what changes is how people organize their production systems and social structures. Drought did not directly wipe out the bison, but it shifted the balance between social needs and environmental capacity. When demands increased while local carrying capacity became less stable, a site that had been adequate for centuries could suddenly feel unsuitable.

The story of Bergstrom illustrates that climate change can trigger structural adjustments within societies, not just short-term behavioral shifts. The hunters responded to uncertainty by changing their choice of location and possibly their patterns of cooperation. This flexibility is what allowed their system to endure over the long term.

In a modern context, these findings offer perspective, the challenge of climate change is not simply about whether resources exist, but about whether the social systems built around them remain compatible with environmental capacity. As in Montana 1,100 years ago, major change can be set in motion by something that seems small—such as the flow of a modest stream. (Sulung Prasetyo)