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  • Monkeys relaxing in a hot spring bath at Jigokudani Yaen-koen in Nagano Prefecture
  • Monkeys in a hot spring bath
  • Monkeys grooming in a hot spring bath
  • Parent and child monkeys relaxing
  • Monkeys at play
  • A monkey with a snowball

January 2022

Snow Monkeys

Monkeys relaxing in a hot spring bath at Jigokudani Yaen-koen in Nagano Prefecture

Opened in 1964, Jigokudani Yaen-koen (Jigokudani Monkey Park) in Nagano Prefecture is a facility where wild Japanese monkeys can be observed up close all year round. Particularly famous in Japan and around the world are the “snow monkeys” that bathe in the natural hot springs in winter.

Monkeys in a hot spring bath

Jigokudani Yaen-koen (below, “Yaen-koen”) is located 850 meters above sea level in the mountains of Yamano­uchi Town in the northern part of Nagano Prefecture. Its setting is a steep rocky gorge, where natural hot springs have gushed forth since ancient times. The park is inhabited by groups of wild Japanese macaques*, a species of monkey endemic to Japan.

Monkeys grooming in a hot spring bath

It is more than sixty years since the late Hara Sogo, who would become the first director of Yaen-koen, began feeding wild monkeys in the vicinity of the Korakukan inn at Jigokudani Onsen. At the time, forests were being cleared for the development of a ski resort in the area, which sees around a meter of snow in winter, and groups of Japanese macaques started appearing in the fields and orchards in the foothills of the mountains near people’s homes. Hara and other locals started feeding the Japanese macaques to stop them raiding the fields and orchards. It was then that they began to think about how they might somehow make use of the monkeys as a resource for tourism. In the meantime, inquisitive young monkeys began to bathe in the hot springs of Korakukan during the snowy winter season, perhaps imitating the onsen guests. Hara and his neighbors had never seen monkeys in a hot spring before, and they came up with the idea of turning this unusual sight into a tourist attraction for the town.

Parent and child monkeys relaxing

Yaen-koen opened in 1964. Three years later, an outdoor hot spring bath for the exclusive use of the monkeys was completed. In 1970, a photograph entitled “Snow Monkeys of Japan” depicting a Japanese macaque soaking in a hot spring in a snowy landscape appeared on the cover of the American magazine LIFE, and their fame spread around the world.

Monkeys at play

“Monkeys actually don’t like to get their bodies wet,” says Takizawa Atsushi, sales manager of Yaen-koen. “This is probably the only place in the world, apart from zoos, where you can see monkeys bathing.”

Currently, some 160 monkeys come to Yaen-koen, of which only around 50 soak in the hot spring. It is said that monkeys will live their whole lives without entering the hot spring bath unless they soaked in the hot water when they were infants.

A monkey with a snowball

Alongside the popular winter sight of the monkeys bathing, Yaen-koen’s appeal lies in the fact that visitors can observe groups of wild Japanese macaques at amazingly close quarters all year round. From spring through fall, visitors can watch the monkeys tending to their infants and young monkeys playing with each other, oblivious to the presence of humans nearby. You might think that in winter, visitors are guaranteed to see monkeys bathing, but that is not so. This is because on fine days the monkeys spend most of their time on the sunny slopes of the mountains, a comfortable place where they can take refuge from the cold without needing to soak in the hot springs and where food is plentiful.

Yaen-koen has set up a live camera to film the monkeys and streams the action over the Internet, so visitors can observe their activities online from anywhere in the world. Sometimes they even get to see the monkeys soaking in the hot spring. Nevertheless, says Takizawa, “If ever you have the chance, I strongly encourage you to come and see firsthand the monkeys playing in the magnificent natural surroundings of Yamanouchi Town.”

* Primates of the Cercopithecoidea (long-tailed monkey) family, endemic to Japan. Japanese macaques live in evergreen and deciduous broad-leaved forests and form matriarchal groups of a dozen or so to a hundred, including adult males, that roam freely in groups.