In each place there are folk tales saying wild animals take a bath to heel their hurt, but it is just a matter of myth.

However, it is true that monkeys in Jigokudani take a bath.

After the success of artificial feeding, they stay in the park longer and have time to relax while waiting for feeding time. One day, a very young monkey accidentally learned to take the open-air bath of Korakukan. Maybe taking a hot bath during cold season was warm and comfortable for him. Other monkeys gradually became to behave in the same manner.

We built an open-air bath as monkeys’ private onsen because it is unfavorable from a hygiene standpoint if monkeys use the same bath with human. Since then monkeys inherit the behavior of bathing for generations.

Why monkeys in Jigokudani take a bath?

*Artificial feeding gave monkeys affluent life
*Cold weather in Jigok-dani
*There are onsen facilities in Jigokudani area

We think that monkeys’ such unique behavior has been generated by several overlapping conditions.

The reason why monkeys take a bath is to protect them from the cold weather. So they are reluctant to take a bath during warm and summer season.

Bathing is just a part of their daily life. Some monkeys do not like to bathing. Eating and having communication with other monkeys are more important than bathing. For monkeys, ‘onsen’ is not must-have item.

Unlike human, they do not wash their body in the bath. They just feel good when they get warm their body in the hot bath. Some monkeys are about to fall asleep. On a very cold and snowy day, many monkeys take a bath, some of them stay in the bath for a couple of hours.

Monkeys do not feel cold after taking a bath.

We, human sweat out from the sweat glands of the skin for thermoregulation so we feel cold if we release heat more than necessary and lose body temperature rapidly. But animals covered whole bodies with fur like monkeys have few sweat glands and they do not sweat so much.

Therefore they do not have sudden change of body temperature.

In addition, they have a developed heat protecting function to survive in the cold region. Their capillary vessels at end of body shrink to avoid heat releasing. That’s why they do not get frost damages even they walk with naked feet on the snow.