A monkey used to to be photographed with tourists, wears a thick coat to protect it from cold in central Kiev, Ukraine January 10, 2017. REUTERS/Gleb Garanich 

A group of monkeys eat flowers and food offered by Buddhist devotees during a New Year religious ceremony at Ruwanwelisaya Stupa in Anuradhapura, Sri Lanka January 1, 2017. REUTERS/Dinuka Liyanawatte 

A Japanese macaque (or so called Snow Monkey) takes a rest on rocks near a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) sits on a tree near a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) looks at a fire near a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) jumps between rocks around a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) takes a rest on rocks near a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

Japanese macaques (or so called Snow Monkeys) hold each other while sitting on rocks near a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino TPX IMAGES OF THE DAY

Japanese macaques (or so called Snow Monkeys) take a rest on a wooden board covering the source of a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) drinks water from a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) takes a rest on rocks after soaking in a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) soaks in a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino

A Japanese macaque (or so called Snow Monkey) sits on a rock inside a hot spring at a valley in Yamanouchi town, Nagano prefecture, Japan, November 30, 2015. REUTERS/Yuya Shino TPX IMAGES OF THE DAY

Snow monkeys sit on a tree in their habitat at New York's Central Park Zoo following an early morning snowfall January 9, 2015. REUTERS/Brendan McDermid (UNITED STATES - Tags: ANIMALS SOCIETY ENVIRONMENT) 

Japanese Macaques (or Snow Monkeys) groom each other in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) groom each other in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

A young Japanese Macaques (or Snow Monkey) touches the camera lens as they gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) gather on a water supply pipe for a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

A Japanese Macaque (or Snow Monkey) soaks in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) groom each other in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL TPX IMAGES OF THE DAY) 

Japanese Macaques (or Snow Monkeys) groom each other in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

A Japanese Macaque (or Snow Monkey) soaks in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

A Japanese Macaque (or Snow Monkey) is groomed as they gather in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

A Japanese Macaque (or Snow Monkey) soaks in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL) 

Japanese Macaques (or Snow Monkeys) gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 20, 2014. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS SOCIETY TRAVEL TPX IMAGES OF THE DAY) 

A baby Japanese Macaque (L), or snow monkey, is held by its mother during a snowfall at a wildlife zoo in Hefei, Anhui province December 26, 2012. A fresh cold snap will hit most parts of China in the coming three days, according to the National Meteorological Center's forecast on Wednesday, Xinhua News Agency reported. REUTERS/Stringer (CHINA - Tags: ANIMALS ENVIRONMENT SOCIETY) 

A baby Japanese Macaque, or snow monkey, eats during a snowfall at a wildlife zoo in Hefei, Anhui province December 26, 2012. A fresh cold snap will hit most parts of China in the coming three days, according to the National Meteorological Center's forecast on Wednesday, Xinhua News Agency reported. REUTERS/Stringer (CHINA - Tags: ANIMALS ENVIRONMENT SOCIETY) 

A baby Japanese Macaque (bottom), or snow monkey, is held by its mother during a snowfall at a wildlife zoo in Hefei, Anhui province December 26, 2012. A fresh cold snap will hit most parts of China in the coming three days, according to the National Meteorological Center's forecast on Wednesday, Xinhua News Agency reported. REUTERS/Stringer (CHINA - Tags: ANIMALS ENVIRONMENT SOCIETY) 

Japanese macaques gather on a tyre at Sapporo Maruyama Zoo in Sapporo, northern Japan, January 18, 2010. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS) 

Japanese macaques gather on a tyre at Sapporo Maruyama Zoo in Sapporo, northern Japan, January 18, 2010. REUTERS/Issei Kato (JAPAN - Tags: ANIMALS IMAGES OF THE DAY) 

Japanese Macaques (or Snow Monkeys) soak in a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS) 

A Japanese Macaque (or Snow Monkey) soaks in a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS) 

A Japanese Macaque (or Snow Monkey) breastfeeds her cub in a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS) 

A Japanese Macaque (or Snow Monkey) soaks in a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS) 

A Japanese Macaque cub (or Snow Monkey) is groomed in a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS) 

A Japanese Macaque (or Snow Monkey) stands near a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS) 

A Japanese Macaque (or Snow Monkey) sits in the snow after climbing out of a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS SOCIETY) 

A Japanese Macaque (or Snow Monkey) soaks in a hot spring in Yamanouchi town, central Japan, December 17, 2009. REUTERS/Pablo Sanchez (JAPAN - Tags: ANIMALS SOCIETY IMAGES OF THE DAY) 

A Japanese monkey soaks in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 2, 2009. REUTERS/Yuriko Nakao (JAPAN) 

Japanese monkeys gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 2, 2009. REUTERS/Yuriko Nakao (JAPAN) 

Japanese monkeys gather to soak in a hot spring at a snow-covered valley in Yamanouchi town, central Japan January 2, 2009. REUTERS/Yuriko Nakao (JAPAN) 

A snow monkey eats frozen fruit after staff at Bioparco zoo gave the animals cool treats during a hot summer day in Rome June 30, 2008. Temperatures in Italy's capital have been hovering around the mid-30 degree Celsius (90 F) mark for the past week. REUTERS/Alessandro Bianchi (ITALY) 

Japanese monkeys gather to soak in a hot spring in a snow-covered valley in Yamanouchi town, central Japan February 17, 2008. REUTERS/Issei Kato (JAPAN) 

A Japanese monkey soaks in a hot spring in a snow-covered valley in Yamanouchi town, central Japan February 17, 2008. REUTERS/Issei Kato (JAPAN) 

Japanese monkeys soak in a hot spring in a snow-covered valley in Yamanouchi town, central Japan February 17, 2008. REUTERS/Issei Kato (JAPAN) 

Japanese monkeys soak in a hot spring in a snow-covered valley in Yamanouchi town, central Japan February 17, 2008. REUTERS/Issei Kato (JAPAN) 

A Japanese monkey soaks in a hot spring in a snow-covered valley in Yamanouchi town, central Japan February 17, 2008. REUTERS/Issei Kato (JAPAN) 

A Japanese monkey soaks in a hot spring in a snow-covered valley in Yamanouchi town, central Japan February 17, 2008. REUTERS/Issei Kato (JAPAN) 

A Japanese monkey soaks in a hot spring in a snow-covered valley in Yamanouchi town, central Japan February 17, 2008. REUTERS/Issei Kato (JAPAN) 

A zookeeper holds a six-months old howler monkey (Aluoatta palliata) named "Nieve" (the Spanish word for "Snow") at the Nicaraguan National Zoo in Managua February 20,2007.The howler Monkey is a rare albino specimen and was found in a forest in the country's Caribbean lowlands.REUTERS/Oswaldo Rivas (NICARAGUA) 

A zookeeper holds a six-months old howler monkey (Aluoatta palliata) named "Nieve" (the Spanish word for "Snow") at the Nicaraguan National Zoo in Managua February 20,2007.The howler Monkey is a rare albino specimen and was found in a forest in the country's Caribbean lowlands.REUTERS/Oswaldo Rivas (NICARAGUA) 

A street photographer's monkey dressed in warm clothes stands near Red Square and Kremlin during a snowfall in Moscow February 13, 2007. REUTERS/Sergei Karpukhin (RUSSIA) 

A Japanese monkey bathes in a steamy hot spring in a snow-covered valley in Yamanouchi town, central Japan March 12, 2006. There are about 200 monkeys in the valley. REUTERS/Kimimasa Mayama 

A Japanese monkey shelters its baby monkey from heavy snow near a hot spring in a snow-covered valley in Yamanouchi town, central Japan March 12, 2006. There are about 200 monkeys in the valley.