An alligator named Muja is seen in its enclosure in Belgrade's Zoo, Serbia, August 14, 2018. Muja is officially the oldest American alligator in the world living in captivity. He was brought to Belgrade from Germany in 1937, a year after the opening of the Zoo. Muja survived three bombings of Belgrade, the Second World War and all hardships the Zoo went through. (Photo by Marko Djurica/Reuters)

A young tiger tries to get at poultry parts hidden in a pumpkin at Magdeburg Zoo, Germany on October 30, 2025. The zoo is celebrating Halloween from October 31, 2025 to November 1, 2025. In addition to the puppet theater, children's carousel and children's train, visitors can carve their own pumpkins, which are then distributed to the zoo animals and serve as food. (Photo by Klaus-Dietmar Gabbert/Avalon)

A blue-throated macaw receives acupuncture and laser therapy treatment at the veterinary hospital in Brasilia Zoo, July 30, 2015. The zoo's veterinary hospital uses acupuncture and laser therapy to improve the health and well-being of animals with chronic diseases. (Photo by Ueslei Marcelino/Reuters)

A tiger yawns next to a piglet at the Sriracha Tiger Zoo, in Chonburi province, Thailand, June 7, 2016. (Photo by Chaiwat Subprasom/Reuters)

A gibbon drinks from a soft drink bottle, given by a tourist, at a zoo in Kunming, Yunnan province, June 18, 2015. (Photo by Wong Campion/Reuters)

A baby Chimpanzee plays in its enclosure at Taronga Zoo July 14, 2006 in Sydney, Australia. (Photo by Ian Waldie/Getty Images)

A zoo keeper feeds Diego, a three month old howler monkey, which is reared at Edinburgh Zoo, July 29, 2008 in Scotland. (Photo by Jeff J. Mitchell/Getty Images)

Central Park Zoo, New York, 1967. (Photo by Garry Winogrand)