TOKYO - Climber traffic fell more than 30 percent in northern Japan's Hokkaido and Tohoku regions between April and June compared with the same period two years earlier, with the sharpest declines seen in areas hit hard by bear attacks, an analysis of smartphone location data on major mountains showed Monday.
The data on climbers to Japan's "hyakumeizan" or 100 famous mountains showed the number in the three-month period fell 34 percent in the Tohoku region of northeastern Honshu and 32 percent on the island of Hokkaido from the same period in 2024. The overall decline across the 100 mountains nationwide was 18 percent.
Ahead of Mountain Day, a national holiday on Tuesday, Tokyo-based IT company Uneri Inc. and Kyodo News analyzed three years of smartphone location data, focusing on people who came within 500 meters of the summits. The data were collected from smartphone apps with users' consent.
In Tohoku, the number of climbers had already fallen 35 percent from 2024 levels in 2025 and remained at roughly the same low level this year.
The sharpest decline was at Hachimantai, which straddles Iwate and neighboring Akita prefectures, where the number of hikers fell 46 percent from 2024. Mt. Adatara in Fukushima Prefecture recorded a 27 percent decline.
In Hokkaido, the decline deepened after hiker traffic fell 18 percent in 2025.
Akita recorded 59 cases of black bear attacks on people, including in urban areas, in fiscal 2025, the most among Japan's 47 prefectures, while Iwate logged 39, the second most, according to the Environment Ministry. A total of nine people died in bear attacks in the two prefectures.
In Hokkaido, hiking trails on Mt. Rausu were temporarily closed after a fatal brown bear attack last summer, while access to some mountains has also been restricted in recent years.
Elsewhere in Japan, climber traffic fell 17 percent in the Kanto region that includes Tokyo, 15 percent in central Japan, 6 percent in western Japan and Shikoku combined, and 3 percent in Kinki.
The number of hikers on Mt. Kumotori, which straddles Tokyo, Saitama and Yamanashi prefectures, fell 33 percent from 2024 levels. Bear attacks have been reported around the mountain.
Kyushu, the southernmost of Japan's four main islands, saw an 11 percent decline, even though bears are believed to be absent there.
Kiyoshi Yamauchi, an associate professor of wildlife management at Iwate University who specializes in bear ecology, said a series of fatal attacks last year and this year may have heightened anxiety among hikers.
"Many bear attacks occur when people are gathering wild vegetables or in areas near homes," Yamauchi said. "Bears in the mountains tend to be wary and often flee when they sense people nearby."
But he warned that sudden encounters on hiking trails or encounters with bears accompanied by cubs can still be dangerous.
"I hope people will take sensible precautions and enjoy hiking without being overly fearful, such as carrying bear bells or whistles and staying on designated trails," he said.
