Enthusiasts skate on a frozen fen in sub-zero temperatures on February 11, 2012 in Sutton, England. (Photo by Oli Scarff/Getty Images)

A 20-year-old Japanese macaque monkey named Monday scratches her eyes while suffering an allergy to pollen from the cedar tree at Awajishima Monkey Centre on March 17, 2013 in Sumoto, Japan. Many monkeys are suffering the effects of hay fever at this time of the year, with the typical symptoms being the same as with humans. According to Awajishima Monkey center this year hay fever is higher than last year, the pollen season is from February to April. (Photo by Buddhika Weerasinghe)

A grizzly bear eats a frozen fruits during a hot summer day at Rio de Janeiro's zoo January 13, 2015. According to a local climate institute, temperatures in Rio de Janeiro on Tuesday rose up to 34 degrees Celsius (93.2 degrees Fahrenheit). (Photo by Sergio Moraes/Reuters)

“I See Sea” by Photographer Dmytriy Dokunov. The frozen Black Sea. Scene of action: Odessa, Ukraine; January, 2012. (Photo by Dmytriy Dokunov)

A woman cartwheels through the Coachella Valley Music and Arts Festival in Indio, California April 10, 2015. (Photo by Lucy Nicholson/Reuters)

A police officer removes a reveler from standing on a post as they guard and clear the street of revelers dressed in holiday themed costumes during SantaCon in New York Saturday, December 12, 2015. As thousands of Santa-suited merrymakers prepare to hit the city's streets and bars, organizers of the annual pub crawl say they're taking more steps than ever to deter naughty behavior. (Photo by Andres Kudacki/AP Photo)

A costumed guest attends WonderCon Anaheim 2015 at Anaheim Convention Center on April 4, 2015 in Anaheim, California. (Photo by Araya Diaz/WireImage)

Delphina Bianchi, 10, sits on the bed of a truck carrying giant pumpkins from her grandfather's John Muller's farm at the Annual Safeway World Championship Pumpkin Weigh-Off Monday, October 12, 2015, in Half Moon Bay, Calif. (Photo by Marcio Jose Sanchez/AP Photo)