This US Coast Guard photo obtained August 24, 2015 shows a polar bear observed off Coast Guard Cutter Healy's stern, on August 23, 2015, while the cutter is underway in the Arctic Ocean in support of Geotraces. Geotraces is Healy's second science mission of the summer, and is an international effort to study the distribution of trace elements in the world's oceans. (Photo by Cory J. Mendenhall/AFP Photo)

Two Indian gharials are seen in their basin in the Prague zoo, Czech Republic, 26 August 2015. In the 1970s the gharial came to the brink of extinction and even now remains on the critically endangered list. Prague zoo is the only Europe zoo breeding them. (Photo by Filip Singer/EPA)

An Indian gharial opens its jaws in its basin in the Prague zoo, Czech Republic, 26 August 2015. (Photo by Filip Singer/EPA)

Giant panda cub Bao Bao is given a cake to enjoy on her second birthday, at Smithsonian's National Zoological Park, in Washington, DC, August 23, 2015. Bao Bao's second birthday comes a day after her mother, 17-year-old Mei Xiang, gave birth to twins, 22 August. This is only the third time a giant panda living in the United States has given birth to twins. (Photo by Michael Reynolds/EPA)

A polar bear eats an ice fruit cake inside its enclosure during a hot summer day at Prague Zoo, Czech Republic, August 23, 2015. (Photo by David W. Cerny/Reuters)

A polar bear eats frozen fruit cake inside its enclosure during a hot summer day at Prague Zoo, Czech Republic, August 23, 2015. (Photo by David W. Cerny/Reuters)

A polar bear eats frozen fruit cake inside its enclosure during a hot summer day at Prague Zoo, Czech Republic, August 23, 2015. (Photo by David W. Cerny/Reuters)

Sumatran rhino Harapan, the only Sumatran rhino in the Western Hemisphere, is seen at the Cincinnati Zoo in this undated handout picture from the Cincinnati Zoo & Botanical Garden in Cincinnati, Ohio. The only Sumatran rhinoceros in the United States will be sent to Indonesia so it can have a chance to mate, an Ohio zoo famous for breeding the endangered species said on Tuesday. Eight-year-old Harapan, one of three Sumatran rhinos born at the Cincinnati Zoo, will move to the Sumatran Rhino Sanctuary later this year, said Dr. Terri Roth, director of its Center for Conservation and Research of Endangered Wildlife. (Photo by Reuters/Cincinnati Zoo and Botanical Garden)

A moose wades in the Vistula river in central Warsaw, Poland August 26, 2015. Local residents reported finding the moose wandering the streets of Warsaw in the morning. (Photo by Kacper Pempel/Reuters)

A smaller of two panda cubs born to Giant Panda Mei Xiang August 22 is fed from a bottle at the Smithsonian's National Zoo in Washington, in this picture taken August 24, 2015. The smaller of twin panda cubs born over the weekend to giant panda Mei Xiang died on Wednesday afternoon, Washington's National Zoo said. (Photo by Shellie Pick/Reuters/Smithsonian's National Zoo)

A Penguin runs out of the ocean after swimming with other penguins at Boulders beach a popular tourist destination in Simon's Town, South Africa, Thursday, August 27, 2015. The penguins on South Africa's west coast are a big tourist attraction, but their numbers have declined and scientists are still debating whether fishing has helped push the species to the brink of extinction. (Photo by Schalk van Zuydam/AP Photo)

A Penguin runs out of the ocean after swimming at Boulders beach a popular tourist destination in Simon's Town, South Africa, Thursday, August 27, 2015. (Photo by Schalk van Zuydam/AP Photo)

Humboldt Penguins are led to the weighing scales with a feed of anchovies to encourage them at London Zoo, in London, Wednesday, August 26, 2015. The Zoo held it's annual weigh-in where the vital statistics of animals were taken in an aid for keepers to detect pregnancies and check the animals general wellbeing. (Photo by Alastair Grant/AP Photo)

Sprocker spaniel Sully with his lego double UK's “best pet” gets Lego double at Legoland Windsor Resort, Britain on August 27, 2015. A Sprocker Spaniel was today officially declared the UK's best pet when he came nose to nose with his perfect Lego double at the Legoland Windsor Resort. One year old Sully was voted the nation's top dog for helping a family deal with life changing tragedy and was nominated by eight year old Ella Harvey. Sully was joined by owners the Harvey family - mum Kerry, dad Gavin, Ella and Millie (6) – who credit their dog with bringing them closer together after Gavin lost both legs on a tour of duty in Afghanistan. The canine topped a nationwide search to find the country's best pet friend and is being honoured with his very own Lego model in the Lego Friends Heartlake City area of the Legoland resort. (Photo by Mikael Buck/REX Shutterstock)

In this photo taken on Tuesday, August 18, 2015, a caretaker feeds chimpanzees on the six mangrove outcroppings that make up Chimpanzee Island, about 50 kilometers (31 miles) southeast of Liberia's capital, Monrovia. These chimpanzees are among 66 that were used for research for years. The New York Blood Center did tests on the chimps for Hepatitis B and other diseases in Liberia in the 1970s, stopping about a decade ago. In March the center stopped payments to care for the animals, according to the Washington-based Humane Society, which is now helping to support the chimpanzees and looking for a long-term solution. (Photo by Abbas Dulleh/AP Photo)

A newly born Zebra baby stands next to her mother at the zoo in Prague, Czech Republic, 28 August 2015. The baby Zebra was born during the morning hours of 28 August 2014 and its s*x and name is still unkown. (Photo by Filip Singer/EPA)

A new-born female square-lipped rhinoceros approaches its mother Keren at the Ramat Gan Safari near Tel Aviv, Israel, 24 August 2015. The yet unnamed rhino was presented to the public as part of a special breeding program of the Safari. (Photo by Abir Sultan/EPA)

A new born female Square-lipped Rhinoceros is seen with her six-year old-mother, Keren, at the Ramat Gan Safari zoo near Tel Aviv on August 24, 2015. (Photo by Menahem Kahana/AFP Photo)

This orphaned badger cub has found an unlikely play pals – a tiny fox cubs who was abandoned by his mothers. The unlikely duo were all found abandoned by within weeks of each other. Tiny Frosty the badger, who is eight weeks old and weighs just two kilograms, was spotted cowering under a tree covered in frost by a dog walker. The walker left the terrified cub alone but when she went back to check on him hours later, she found he was still there. She called the the Wildlife Aid rescue centre in Leatherhead, Surrey, UK, who rushed to woodland in Essex to recover little Frosty. (Photo by Splash News and Pictures)

She may be only three-weeks old, but a rare baby zebra born at ZSL Whipsnade Zoo is already making her mum earn her racing stripes. The as yet unnamed Grevy's zebra, born on July 17, can be spotted giving mum Henna the run-around and gambolling in the paddock they share with the rest of the herd, including dad Abeba. Africa section team leader, Mark Holden, said: “Henna is doing a great job of looking after her new arrival. It's her first-born so she's very protective but both of them are doing really well. The foal can often be seen up and running with the rest of the herd or having a rest with mum”. The leggy youngster was born with brown stripes that will turn black as she matures - her striped pattern is as unique as a fingerprint; no two zebra patterns are the same. She is the 27th foal to be born at the Zoo as part of a European Endangered Species Programme and is an important addition to the species which is classified as “Endangered” on the IUCN Red List of Threatened Species with only an estimated 2,500 animals remaining in the wild. (Photo by Jeff Moore/Splash News)

Adorable Pygmy Slow Loris twins receive their first medical examination. The tiny, nocturnal primates were born August 22 at El Paso Zoo, Texas. The unnamed pair where pictured during their first medical exam before they were spotted playing with their mother Kym Ly. The male weighed in at 52.4 grams and his sister, a petite 43.5 grams. (Photo by Splash News/El Paso Zoo)

This huge male orangutan is having a right old laugh as he squints his eyes and shows his huge teeth. The orangutan, called Bimbo, was relaxing on a platform around 5m high in his enclosure when he broke out into a laugh. But his happy smile soon disappeared when another orangutan came over to see what was going on. Bimbo – the only male in the group of five apes at Leipzig Zoo, in Germany - appears to be laughing in much the same way as a human would. (Photo by Martina Radtke/Solent News)

A Khon Kaen Zoo handout photo made available on 28 August 2015 shows a male baby, as yet unnamed, white albino wallaby sitting inside his mother's pouch at Khon Kaen Zoo, Khon Kaen province, Thailand, 17 August 2015. Wallabies are a small sized member of the same taxonomic family as kangaroos and are native in Australia, New Guinea and nearby islands. (Photo by Khon Kaen Zoo/EPA)