Persistent bear activity in Japan has led to the cancellation of several outdoor events, even as the hibernation season begins. Sightings near populated areas remain higher than usual, prompting experts to urge continued vigilance into early January.
Japan is facing an unprecedented bear crisis in the autumn and early winter of 2025, with brown bears and Asiatic black bears appearing not only on the fringes but in the centers of urban areas in the Tohoku region. By the end of October, at least 12 people had died in bear encounters, marking the worst year on record.
Two main forces are driving this surge. In areas with frequent sightings, the acorn crop—a key autumn food source for bears—has failed across multiple oak species, forcing bears to roam far beyond their usual ranges. A deeper, long-term factor is the expansion of bears' distribution in Japan, which nearly doubled in size over the 40 years leading up to 2018. As rural populations shrink and age, forests are reclaiming abandoned settlements, with untended persimmon and chestnut trees becoming attractive food sources that draw bears into human areas.
Specific impacts include the cancellation by the Kofu tourism association of the 15th Takeda no Mori Trail Running Race scheduled for December 14. Around 900 runners were expected for the event, which looped through the satoyama foothills of Kofu with views of Mt. Fuji and the Southern Japanese Alps. An association official stated, “It was a difficult decision, but we prioritized the safety of the participants and staff.”
Additionally, an environmental learning session in Nagatoro, Saitama Prefecture, was suspended on Saturday, where elementary and junior high school students were to experience log-cutting and other outdoor activities. In mid-November, Aquarium Asamushi in Aomori halted its nighttime operations, a period when bear activity typically heightens.
Kazuhiko Maita, head of the Institute for Asian Black Bear Research and Preservation in Hiroshima Prefecture, warned, “They could appear near populated areas as late as early January next year, making it essential to remain vigilant. Even if they begin to hibernate, noise and other disturbances could wake them up.” Normally, bears hibernate deep in the mountains in large numbers during this season, but recent years have seen young bears venturing into urban areas for food and hibernating in shrines or parks after the New Year.
These events highlight how landscape changes from depopulation are reshaping wildlife-human interactions.