Hong Kong (CNN) — An An, the world's oldest male giant panda in captivity, died Thursday following health problems at age 35.
The panda was euthanized to prevent further suffering, Hong Kong's Ocean Park said in a statement. His "cleverness and playfulness" would be dearly missed, the park's chairman Paulo Pong said.
An An was gifted to the theme park 23 years ago by the Chinese central government, along with Jia Jia, a female believed to be the world's oldest ever giant panda before her death in 2016 at age 38.
The pair were seen by millions of tourists and schoolchildren over the years, many of whom posted their memories of An An online Thursday in photos and videos.
A panda's average life span in the wild is 14-20 years, but they can live far longer in captivity, according to wildlife conservationists World Wide Fund for Nature (WWF).
Pong said that An An's survival beyond the average life expectancy demonstrates the theme park's ongoing commitment to giant pandas.
The theme park still houses two other giant pandas -- female Ying Ying and male Le Le -- which were gifted by the Chinese government in 2007.
China has spent half a century attempting to boost the population of its iconic animals, creating sprawling panda reserves across several mountain ranges in an effort to save them from extinction.
Giant pandas are notoriously hard to breed in captivity, but after years of decline, their numbers in the wild have increased in recent years.
In 2017 the International Union for Conservation of Nature (IUCN) upgraded the species from "endangered" to "vulnerable" after their population grew nearly 17% over the previous decade. That move was mirrored by the Chinese government last year after the wild giant panda population increased to 1,800.
In China, pandas are considered an umbrella species, which means experts believe measures to protect them will help protect other species, as well as the larger ecosystem.