A study has solved the mystery of why Indigenous hunters stopped using the Bergstrom site in central Montana around 1,100 years ago, despite abundant bison in the area.
Researchers found that recurring severe droughts reduced water availability at a small nearby creek needed to process large numbers of animals. The site had been used intermittently for about 700 years before abandonment.
Dr. John Wendt, lead author from New Mexico State University, said hunters ceased using the location due to environmental stressors and shifting social pressures. Bison remained plentiful, vegetation stayed the same, and fire activity showed no major change.
The study, published in Frontiers in Conservation Science, combined excavation, sediment analysis, and climate reconstructions. It noted that hunting groups were moving toward larger coordinated operations that required reliable water and other resources.
Wendt added that long-term success depended on adapting strategies across generations in response to climate instability.