A West African Slender-snouted Crocodile is pictured in its enclosure at the zoo of Abidjan, Ivory Coast September 9, 2016. (Photo by Luc Gnago/Reuters)

The first jaguar litter since 1975 was born at the Milwaukee County Zoo to Stella and Pat on November 13, 2013. The litter was on public display for the first time on March 13 when the jaguar baby's names were released. Belize schoolchildren named one Zean, which is the end of Belizean, and a public contest named the other B'alam, which means "great and powerful king" in Mayan. Photo: Stella the mother and her cub Zean rest together at The Milwaukee County Zoo. (Photo by Rick Wood)

Karishma, a 13 year old female Asian elephant, paints at an easel in her enclosure at ZSL Whipsnade Zoo on September 20, 2011 in Dunstable, England. A selection of Karishma's artwork will go on display at the Zoo this weekend to celebrate Elephant Appreciation Day. (Photo by Oli Scarff/Getty Images)

Gorillas sit next to a ruler during a photocall for the annual weigh-in at London Zoo in London, Britain August 24, 2017. During the weigh-in, animals across the zoo have their vital statistics recorded including their height and weight and the information is then shared with zoos across the world to help zookeepers compare important information on thousands of endangered species. (Photo by Neil Hall/Reuters)

In this image provided by the Pairi Daiza park, giant panda Hao Hao holds her newborn baby in her mouth at the park in Brugelette, Belgium, on Thursday, June 2, 2016. With the help of the Chinese government Hao Hao and her mate Xing Hui arrived in Belgium two years ago and Pairi Daiza adapted its park to build a bamboo forest for them. (Photo by Benoit Bouchez/Pairi Daiza via AP Photo)

A Western Lowland Gorilla baby named “Mjukuu”, that was born in October last year, rides on the back of its Mother “Mbeli” in their enclosure at Taronga Zoo in Sydney, Australia, May 19, 2015. The baby gorilla was born six days ago, and is the second sired by the zoo's new Silverback, Kibali, who arrived from France in 2012. (Photo by David Gray/Reuters)

“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)