For the Japanese, there is nothing more relaxing than a soothingly hot bath in the onsen.

But not only they love their baths fed by natural hot springs.

At Izu Shaboten Zoo in Tokyo's neighboring Saitama Prefecture, capybaras frolic among visitors with their babies in a hot outdoor pool in winter, warming up and relaxing in the cold air, a spokeswoman said Tuesday.

On the occasion of the 40th anniversary, one of the capybaras ceremoniously cut a ribbon of grass, after which the cute animals climbed into the water, in which citrus fruits were floating.

It had been in the winter of 1982 when an employee while cleaning the facility with hot water noticed a capybara relaxing in a hot pool.

Since then, the bathing animals have been an annual attraction for visitors.

The sight of the capybaras enjoying the hot water also has a relaxing effect on visitors, it said.

The bathing animals can be seen until April 2nd next year.

But they're not the only ones who love hot baths.

Wild snow monkeys at Japan's famous Jigokudani Monkey Park also indulge in hot baths in the onsen during the winter months under the curious gaze of tourists.

Apparently they don't do that primarily to warm up, as one might think.

In fact, female Japanese macaques, just like humans, seem to benefit from onsen baths in relieving stress in cold weather, scientists from Kyoto University found a few years ago.

This is likely to affect their chances of reproduction and survival.