This 51-year-old pygmy hippo just set a world record

a pygmy hippo shows teeth in seemingly happy way — Hannah Shirley, we salute you.

*Image: San Diego Humane Society*

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How does a pygmy hippo celebrate her birthday? With a watermelon treat and party decorations, of course.

The charming Hannah Shirley is the world’s oldest pygmy hippopotamus to ever live in managed care. Hannah has called the San Diego Humane Society’s Ramona Wildlife Center home since 2002 when she was rescued from a private backyard in Escondido, California. In the wild, the endangered pygmy hippos live an average of 30-50 years, but on May 25, 2025, Hannah surpassed the previous record of 51 years, 6 months, and 2 days.

“Hannah was born on Nov. 22, 1973, and is recognized in the Association of Zoos and Aquariums (AZA) Regional Studbook as animal #365, which tracks all pygmy hippos living in managed care around the globe,” a statement from the San Diego Humane Society explains.

hippo sniff balls surrounded by party decorations — Mmmm, leafy greens and watermelon. *Credit: San Diego Humane Society* Phil Tani

Hannah Photos — Hannah now lives in a 13,000-square-foot paddock. *Credit: San Diego Humane Society* SDHS

Pygmy hippos enjoyed the internet spotlight in 2024 with the birth of a feisty, bug-eyed calf named Moo Deng in Thailand and the fun-size pachyderm Haggis in Scotland.

The species is native to the swamps and forests of West Africa, mostly in Liberia. Only about 2,500 currently remain in the wild due to habitat loss from logging, minding, and other human activities. In the North America, only a few dozen live in managed care facilities, including at the Pittsburgh Zoo & Aquarium in Pennsylvania and the Lincoln Park Zoo in Chicago, Illinois.

“Every day with Hannah Shirley is a gift,” said Autumn Welch, Wildlife Operations Manager at the Ramona Wildlife Center, said in a statement. “Her playful spirit, resilience and sweet personality make her a truly special ambassador for her species — and a symbol of how excellent care can help animals thrive far beyond what’s expected.”