A White Bengal tiger yawns in its enclosure at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A brown bear looks at visitors from its enclosure at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A baby black cap capuchin monkey is seen hanging to its mother at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A black cap capuchin monkey plays with some food in its enclosure at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





African lions are seen in their enclosure at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A White Bengal tiger yawns in its enclosure at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A grey crowned crane looks at visitors from its enclosure at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A baby black cap capuchin monkey is seen hanging to its mother at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A black cap capuchin monkey plays with some food in its enclosure at the Olmense Zoo in Olmen, Belgium, September 2, 2015. (Photo by Yves Herman/Reuters)





A leopard leaps into a muddy waterhole to catch a fish on August 13, 2015, in the Savuti Channel in Botswana. A leopard leaps into a muddy waterhole to catch a fish in the Savuti Channel in Botswana. The spotted predator stood poised waiting for a fish to appear – before leaping in ferociously with lightening reflexes. Coated in a layer of thick dark mud the big cat emerged from the water clutching the fish in its jaws. The fishing leopards of Savuti are known for their unique skills in catching fish – but have rarely been photographed. (Photo by Greatstock/Barcroft Media)





A leopard leaps into a muddy waterhole to catch a fish on August 13, 2015, in the Savuti Channel in Botswana. (Photo by Greatstock/Barcroft Media)





Anju, a Western Lowland Gorilla, holds her week-old newborn in the Gorilla World habitat at the Cincinnati Zoo & Botanical Garden, Thursday, September 3, 2015, in Cincinnati. The baby, who has yet to be named, is the 50th gorilla born at the zoo since 1970. (Photo by John Minchillo/AP Photo)





Babies of banded mongoose, born weeks ago, play together in the zoo Pilsen, Czech Republic, September 3, 2015. (Photo by Pavel Nemecek/CTK via ZUMA Press)





A mink sniffs the air as he surveys the river beach in search of food, in meadow near the village of Khatenchitsy, 65 kilometers (40 miles) northwest of Minsk, Belarus, Friday, September 4, 2015. (Photo by Sergei Grits/AP Photo)





A caretaker washes down elephants at the mobile Diva circus in the town of Molodechno, some 70 kilometers northwest of Minsk on September 3, 2015. (Photo by Sergei Gapon/AFP Photo)





An orangutan named “Jacky”, who originated in Borneo, is pictured during celebrations marking his 38th birthday at Bali Zoo in Gianyar on the Indonesian resort island on September 4, 2015. Orangutans, native to Borneo as well as Indonesia's Sumatra island, are faced with extinction from poaching and the rapid destruction of their forest habitat, driven largely by land clearance for palm oil and paper plantations. (Photo by Sonny Tumbelaka/AFP Photo)





Cheetah female Wazi carries one of her four cubs in the enclosure in Opole Zoo in Opole, Poland, 04 September 2015. After 10 years, eight cheetah cubs were born in Opole Zoo from two female cheetahs Wazi and Mambo. (Photo by Krzysztof Swiderski/EPA)





Bantam trained by John O'Shea for Godolphin cools down after a Moonee Valley trackwork session at Moonee Valley Racecourse on September 1, 2015 in Melbourne, Australia. (Photo by Vince Caligiuri/Getty Images)