Pierre Thivillon (R), director of the zoological park of Saint-Martin-La-Plaine and his wife Eliane look at Digit, an 18-year-old female gorilla, on August 19, 2016, in Saint-Martin-La-Plaine between Lyon and Saint-Etienne, southeastern France. The zoological park of Saint-Martin-La-Plaine is a shelter for beasts seized by the justice. (Photo by Philippe Desmazes/AFP Photo)

A female hippopotamus named “Mali”, which means Jasmine, eats fruits arranged to look like a cake during her 50th birthday celebration at Dusit Zoo in Bangkok, Thailand September 23, 2016. (Photo by Chaiwat Subprasom/Reuters)

Award-winning photographer Alex Bernasconi has captured thousands of images – from hiding hippos to wandering zebras – in his travels across Africa. His amazing work features in a new edition of his book Wild Africa. These amazing pictures create a snapshot of the life of some of the planet’s most spectacular animals and natural habitats. Photo: “Wild Africa”. (Photo by Alex Bernasconi)

Inmates ride in a bus out of the Cojutepeque prison in El Salvador, Thursday, June 16, 2016. This prison, which houses more than a thousand 18th street imprisoned gang members, will be closed down by the government, since it has been unable to prevent the amount of illegal activities happening inside the prison walls. Inmates will be relocated to other medium-security prisons. (Photo by Salvador Melendez/AP Photo)

A hyena cub got a mouthful from his mum after it appears he got a right telling off. Michael Raddall, a animal enthusiast and wildlife photographer from South Africa, snapped the mum and cub at the Timbavati game reserve in South Africa while on safari at the Umlani Bush camp. (Photo by Michael Raddall/Caters News Agency)

A huge colony of Pacific Walrus on Arakamchechen Island in the Northern Bering Sea. (Photo by Francois Gohier/Ardea/Caters News)

(L-R) Actors Oscar Sinela, Luis Fernandez, Ursula Corbero, Amaia Salamanca, Maxi Iglesias and Alba Ribas attend “XP3D” premiere at the Callao cinema on December 27, 2011 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

A koala soaked by floodwaters sits atop a fence post to escape the deluge in the town of Stirling in the Adelaide Hills of South Australia in this picture taken September 14, 2016. (Photo by Russell Latter/Reuters)