A young visitor interacts with a baby hippopotamus swimming in its enclosure at the Berlin Zoo on January 1, 2018. Tourists and locals flocked to the zoo in the German capital on the unseasonably warm first day of the year. (Photo by Odd Andersen/AFP Photo)

Confiscated rare and protected wildlife products such as these stuffed Sumatran tiger skins are burned and destroyed during a ceremony by government forestry and wildlife officials in Banda Aceh, Aceh province, Indonesia May 23, 2016 in this photo taken by Antara Foto. (Photo by Irwansyah Putra/Reuters/Antara Foto)

In this August 1, 2014 photo provided by the National Park Service are male caribou antlers in the Oolah Valley, likely the result of a grizzly kill as he migrated south for the winter at the Arctic National Park and Preserve in Alaska. The nation's northernmost national park says its new management plan will have to consider the effects of a new industrial road to the mining district of Ambler, the first road that would be constructed within its Maryland-sized boundaries. (Photo by Cadence Cook/AP Photo/National Park Service)

Lutricia Bock of Germany falls down as she performs during the ladies short program at the ISU European Figure Skating Championship in Bratislava, Slovakia, January 27, 2016. (Photo by David W. Cerny/Reuters)

A homeless street child looks in the window of a car in Jammu, India, Friday, January 6, 2017. Some 800 million people in the country live in poverty, many of them migrating to big cities in search of a livelihood and often ending up on the streets. (Photo by Channi Anand/AP Photo)

A man is silhouetted as he stands on a walkway in the sky lobby at the Chancellery, the seat of German Chancellor Angela Merkel (not pictured) in Berlin, May 7, 2014. (Photo by Thomas Peter/Reuters)

The sun rises over St Mary's Lighthouse in Whitley Bay on the Northumberland coast as a flock of Lapwing seabirds fly past on Wednesday, September 30, 2015. (Photo by Owen Humphreys/PA Wire)

This photo provided by Netflix/naturepl.com and WWF-International shows an African Elephant (Loxodonta africana) in front of double rainbow, in Masai Mara, Kenya, included in the Netflix natural history series, “Our Planet”, in collaboration with Silverback Films and WWF. The eight-part series debuts in 2019. (Photo by Andy Rouse/Naturepl/WWF-International/Netflix via AP Photo)