2016 is the year of the monkey in the Chinese calendar, and it has begun with numerous news reports featuring these creatures -- and other furry beasts -- taking winter dips in hot springs and baths. Which brings up some questions: How do the animals enjoy the experience of an outdoor soak, for starters? And, given their lack of, err, attire, do they not end up feeling chilled?
A visit in mid-December of last year to the Jigokudani Yaen-Koen Wild Snow Monkey Park in the town of Yamanouchi, Nagano Prefecture -- which is famous for being the only facility worldwide where the wild primates may be seen taking baths -- indeed provided glimpses of several Japanese macaques, which are otherwise known as snow monkeys, hanging out inside outdoor hot springs pools amidst dancing white flurries.
The pairing of monkeys and hot springs is a phenomenon that dates back to 1963 -- and it came about by pure happenstance. After an apple that was being fed to a baby monkey fell into a pool, the animal climbed in to retrieve it -- and loved the warmth of the water so much that its larger monkey counterparts soon began coming to try out the experience for themselves.
A closer look at bathing monkeys reveals that they hang on to the sides of the pools while bathing. "This is their basic pose," explains Kayo Miyata, an employee at the monkey park. Their hands release heat -- serving as something of a radiator -- Miyata explains.
Because monkeys do not have many sweat glands, they are unable to lower their body temperature by sweating. And due to a special cold-weather bodily mechanism whereby their blood vessels rapidly constrict, which locks in heat, they don't end up feeling cold after their baths.
Miyata adds, however: "For the most part, they don't really like to get wet." This means that on days that are not especially chilly, the monkeys are unlikely to go in for a dip.
At Itozu No Mori Zoological Park in the city of Kitakyushu, which experiences far milder winter weather than Nagano, the area set up for monkeys during the winter season three years ago has included an outdoor bathing pool -- but few of the animals showed interest. As a result, the initiative has not been repeated this year.
Even more enamored than monkeys with warm baths is the capybara -- otherwise known as the world's largest rodent. The capybara bathing trend began at Izu Shaboten Park in the city of Ito, Shizuoka Prefecture, which installed a "capybara rotenburo", or outdoor bath, in 1982 -- an idea that caught on among zoos nationwide around seven or eight years ago. At present, capybaras at a total of some 30 facilities around the country are able to enjoy hot springs or bath time.
The capybaras' predilection toward chillaxing in warm baths is likely rooted in their natural aversion to the cold, as well as the fact that they are already accustomed to performing many of their life functions inside the water: pooping, as well as taking to rivers in order to hide from its natural predators, to name two.
"Because the capybara's nose, eyes and ears lie flat, the animal is able to stay for hours with half of its face submerged in water," explains Rieko Tanaka, assistant director of the Saitama Children's Zoo in Higashimatsuyama, Saitama Prefecture. "This also helps improve their health, by helping remove dandruff, for example."
Meanwhile, the Japan Racing Association (JRA) utilizes hot springs for purposes including rejuvenating tired horses following competition. With the warm baths said to be proven to calm the animals' heart rate and allow their parasympathetic nerves to relax, Yuhiro Ishikawa of JRA's Equine Research Institute Rehabilitation Research Center commented, "Except for animals such as cats that are known to be water-averse, the effect on just about all mammals is likely going to be the same."