Light sculptures glow in the dark at the zoo in Cologne, Germany, 04 December 2019. The artworks are on display at the zoo as part of the China Light Festival that runs until 09 January 2020 and features more than 70 light installations on the zoo grounds. (Photo by Sascha Steinbach/EPA/EFE)

“Happy Feet” the emperor penguin that washed up on the Kapiti Coast last week, undergoes a medical examination at Wellington Zoo on June 29, 2011 in Wellington, New Zealand. The young penguin landed on NZ shores last week, after traveling over 3,000 kilometres from the antarctic. The ill penguin was operated on at Wellington Zoo several times this week to remove sand and sticks from it's stomach with hopes it will recover fully. A team of experts is likely to decide today, whether the bird will remain in captivity in New Zealand, or be transported back the the antarctic. (Photo by Hagen Hopkins/Getty Images)

A Sumatran Tiger tears apart a wrapped Christmas present at Taronga Zoo on December 21, 2011 in Sydney, Australia. Animals received Christmas themed enrichment foods as part of the Zoo's regular program to encourage the animals to forage for food and help improve hunting abilities. (Photo by Brendon Thorne/Getty Images)

A Sumatran Tiger looks at visiting children from it's enclosure during the ZSL London Zoo's annual stocktake of animals on January 5, 2015 in London, England. The zoo's annual stocktake requires keepers to check on the numbers of every one of the 800 different animal species, including every invertebrate, bird, fish, mammal, reptile, and amphibian. (Photo by Dan Kitwood/Getty Images)

Nekama, a baby North Chinese leopard, emerges from a basket at her official presentation to the media at Tierpark zoo on March 15, 2011 in Berlin, Germany. Nekama was born on January 7, 2011 and currently weighs 4.5 kg.

A newly born Indian white tiger cub yawns in its enclosure at Liberec Zoo, Czech Republic, April 25, 2016. (Photo by David W. Cerny/Reuters)

Zookeeper Michael Horn holds up Kit and Kitty, the twin red pandas born in June on the first day of their introduction into their new enclosure at Tierpark Zoo on September 13, 2011 in Berlin, Germany. The red panda (Ailerus fulgens) is a rare mammal native to the eastern Himalayas and southwestern China. (Photo by Sean Gallup/Getty Images)

A penguin swims in its enclosure during a photocall to promote London Zoo's annual stock take of animals on January 4, 2012 in London, England. The zoo's stocktake takes place annually, and gives keepers a chance to check on the numbers of every one of the animals from stick insects and frogs to tigers and camels. (Photo by Dan Kitwood/Getty Images)