FILE: Even monkeys need a spa day, Japan study finds Japan's "snow monkeys" are known for their love of hot springs. It was long assumed that the blissed-out bathers were simply trying to warm up during the chilly winter months. But experts who observed 12 female Japanese macaques in 2014 at the Jigokudani Yaen-Koen monkey park in Nagano found that stress levels in the monkeys were about 20 percent lower on average after bathing. FILE IMAGES