Frost covers the ground in Richmond park as deer graze on bracken at sunrise in south west London on November 29, 2016. (Photo by Justin Tallis/AFP Photo)





An undated handout picture made available by the Symbio Wildlife Park on 28 November 2016 shows three Pygmy Marmoset monkeys including an adult male, a female juvenile and a four-week-old baby, at the Symbio Wildlife Park in Helensburgh, South of Sydney, New South Wales, Australia. Officers were called to the wildlife park in Helensburgh on 26 November, after staff discovered the monkeys were missing from their enclosure. According to reports on 27 November, two men have been charged with stealing the three rare monkeys after they were found while driving south-west Sydney with one of the missing monkeys, the four-week-old one. Wollongong Police found the missing female juvenile, Sofia, in the Campbelltown area on 27 November, and returned her to the care of the zoo. The male marmoset, father “Gomez”, was reported still missing. (Photo by EPA/Symbio Wildlife Park)





A swan drinks from a hole in the frozen lake in Warminster Lake Pleasure Grounds, as the country wakes up to sub-zero temperatures, on November 30, 2016 in Wiltshire, England. Sennybridge in Wales recorded the lowest temperature of the season overnight, with the Met Office reporting a low of -9.4C. (Photo by Matt Cardy/Getty Images)





A one-month-old baby rhinoceros strolls through its enclosure with its mother at the Cerza Zoo in Hermival-les-Vaux, northwestern France, on November 29, 2016. (Photo by Charly Triballeau/AFP Photo)





A gull tries to land on an occupied pole at the river Main in Frankfurt, Germany, Tuesday, November 29, 2016. (Photo by Michael Probst/AP Photo)





A seagull flies into the low sun over the river Main in Frankfurt, Germany, 30 November 2016. (Photo by Frank Rumpenhorst/DPA)





File - In this Monday, October 5, 2015, file photo, a black-footed ferret looks out of a crate used to take it to a site to be let loose during a release of 30 of the animals by the U.S. Fish and Wildlife Service at the Rocky Mountain Arsenal National Wildlife Refuge in Commerce City, Colo. Dozens of slinky, ferocious and rare ferrets are settling in and making babies at a wildlife refuge outside Denver one year after they were released there.
(Photo by David Zalubowski/AP Photo)





In this Monday, October 5, 2015, photo, a black-footed ferret belts out warning during a release of 30 ferrets by the U.S. Fish and Wildlife Service at the Rocky Mountain Arsenal National Wildlife Refuge in Commerce City, Colo. Dozens of slinky, ferocious and rare ferrets are settling in and making babies at a wildlife refuge outside Denver one year after they were released there. (Photo by David Zalubowski/AP Photo)





Orangutan Fei Fei holds a male cub in her arms at Shanghai Zoo on November 25, 2016 in Shanghai, China. Orangutan Fei Fei gave birth to a male cub at Shanghai Zoo on October 26. The male cub's father Bin Bin and his mother Fei Fei came to Shanghai Zoo from Philippines in July in 2012. It's the first successful reproduction of Orangutan at Shanghai Zoo. (Photo by VCG/VCG via Getty Images)





A male elk crosses the Yellowhead Highway, a route roughly followed by Kinder Morgan's Trans Mountain Pipeline through the Rocky Mountains, in Jasper National Park, Alberta, Canada November 14, 2016. (Photo by Chris Helgren/Reuters)





Young bull elk lock antlers while jousting near the Yellowhead Highway, a route roughly followed by Kinder Morgan's Trans Mountain Pipeline through the Rocky Mountains, in Jasper National Park, Alberta, Canada November 14, 2016. (Photo by Chris Helgren/Reuters)





Young bull elk lock antlers while jousting near the Yellowhead Highway, a route roughly followed by Kinder Morgan's Trans Mountain Pipeline through the Rocky Mountains, in Jasper National Park, Alberta, Canada November 14, 2016. (Photo by Chris Helgren/Reuters)





An urban fox walks alongside the Mall in central London, Britain, November 29, 2016. (Photo by Toby Melville/Reuters)





An urban fox walks alongside the Mall in central London, Britain, November 29, 2016. (Photo by Toby Melville/Reuters)





An urban fox walks alongside the Mall in central London, Britain, November 29, 2016. (Photo by Toby Melville/Reuters)





A Seagull flies over water in St. Stephen's Green in Dublin, Ireland November 29, 2016. (Photo by Clodagh Kilcoyne/Reuters)





Deer graze at dawn on the coldest day the year so far according to the Meteorological Office, in Richmond Park in west London, Britain, November 30, 2016. (Photo by Toby Melville/Reuters)





Deer graze at dawn on the coldest day the year so far according to the Meteorological Office, in Richmond Park in west London, Britain, November 30, 2016. (Photo by Toby Melville/Reuters)





Walker a seven year old polar bear plays in an icy pond at the RZSS Highland Wildlife Park in Kincraig, Kingussie, Scotland, Britain November 30 2016. (Photo by Russell Cheyne/Reuters)





Walker a seven year old polar bear plays in an icy pond at the RZSS Highland Wildlife Park in Kincraig, Kingussie, Scotland, Britain November 30 2016. (Photo by Russell Cheyne/Reuters)





Walker a seven year old polar bear shakes water from his fur as emerges from the icy pond at the RZSS Highland Wildlife Park in Kincraig, Kingussie, Scotland, Britain November 30 2016. (Photo by Russell Cheyne/Reuters)





A lion yawns in the zoo in Frankfurt, Germany, Friday, December 2, 2016. (Photo by Michael Probst/AP Photo)





A four-month-old white lion cub cuddles up to its father Sam inside their enclosure at a zoo in Tbilisi on November 30, 2016. (Photo by Vano Shlamov/AFP Photo)