Monkeys go for Spa
therapy to fight weather
stress,WHAT ABOUT YOU?
By InnoHEALTH Editorial Team
Y
ou might be virtually on
frypan in scorching summer
months following valuating
mercury and grope for
solutions to fight hot climate stress in
India. But in contrast, Snow monkeys
in Japan ward off weather stress by
regular bath in hot springs, a latest
study says.
Japanese macaques, also known as
snow monkeys, have been enjoying
regular baths in the hot spring at
Jigokudani in Japan for decades – and
have even become a popular tourist
attraction.
A team of researchers led by Rafaela
Takeshita of Kyoto University in Japan
have now published the first study
to scientifically validate the benefits
of this behaviour. These findings
indicate how behavioural flexibility
can help counter cold-climate stress
and have likely implications for
reproduction and survival. The study
is available in Primates, the official
journal of the Japan Monkey Centre,
which is published by Springer.
Japanese macaques (Macacafuscata)
are the most northerly species of
nonhuman primates in the world
and have adapted to extremely cold
winters.
Researchers believed that those
living in the Jigokudani Monkey Park
in Nagano maintain their normal
body temperature due to having
thicker and longer fur during winter.
These primates are also the only
group of monkeys known to take hot
spring baths, a behaviour that was
first observed in 1963 when a young
female was seen in an outdoor hot
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Volume 3 | Issue 3 | July-September 2018
spring belonging to a nearby hotel
one snowy day.
Other monkeys soon copied this
behaviour, and for hygienic purposes,
the park management has since built
a hot spring for the exclusive use of
the monkeys. By 2003, one in every
three females in the group bathed
regularly in winter.
Although the fact that snow monkeys
bathe more often during winter
suggests that they use the hot spring
to stay warm, to date no physiological
is known to influence concentrations
of glucocorticoids, which belong to
the family of steroid hormones.
The results confirmed that female
snow monkeys use the hot spring
more often in winter than in spring,
and especially during colder weeks.
Dominant females benefited from
their status and spent longer time
bathing, but they were also involved
in more aggressive conflicts, resulting
in higher energy expenditure than
subordinate females. But taking a
spa reduced stress hormone levels in
those females.
So high social status in this group
of snow monkeys has a trade-off
between the costs of high rank
position and the benefits from a hot
spring, which is advantageous for
conserving energy by reducing loss of
body heat and lowering stress levels.
data had been collected to support
this idea. Takeshita and her colleagues
studied twelve adult females during
the spring birth season, from April
to June, and winter mating season,
from October to December. They
determined how much time the
monkeys spent in the hot springs,
and which monkeys bathed the most.
The researchers also collected faecal
samples during times of extreme cold
and analysed the concentration of
faecal glucocorticoid (fGC) metabolite
present. This was done because
thermoregulatory stress and the
management of a body temperature
“This indicates that, as in humans,
the hot spring has a stress-reducing
effect in snow monkeys,” says
Takeshita, who believes that further
investigation using serum or saliva
samples might be useful to detect
whether there are any further short-
term changes in stress levels.
“This unique habit of hot spring
bathing by snow monkeys illustrates
how behavioural flexibility can help
counter cold-climate stress, with
likely implications for reproduction
and survival.”
In addition, Takeshita and her
colleagues found that the around 500
visitors per day, who watch the snow
monkeys bathe, had no effect on the
levels of stress hormones released.