HARRY THE GORILLA | PHOTO BY PAUL A. SELVAGGIO

Harry, a western lowland silverback gorilla who had lived at the Pittsburgh Zoo & Aquarium for most of his 33 years, has died of heart disease.

Born in 1991 at the Cincinnati Zoo and arriving in Pittsburgh the next year, Harry was the eldest in the zoo’s group of six gorillas. He died Tuesday of a “sudden cardiac event,” despite what the zoo called valiant efforts to resuscitate him.

Harry had been treated for heart disease since 2022, and zoo officials had been consulting with the Great Ape Heart Project, a group of specialists based at the Detroit Zoo that focuses on understanding and treating heart disease in great apes.

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He was a favorite among zoo staff and visitors.

“Harry was amazing with all of the gorilla ‘kids’ and was vigilant and protective with them,” recalled Curator of Mammals Kelsey Forbes, in a statement. “He was an absolutely special boy and had the best laugh of all our gorillas.”

Forbes added that Harry was a gentle gorilla who took quickly to becoming both troop leader and a paternal figure after the passing of 31-year-old Mrithi in 2024; Mrithi, another silverback whose name meant “prince” in Swahili, was the first gorilla ever born at the zoo.

The hearts of gorillas are similar to humans and are highly susceptible to heart disease, according to the Association of Zoos and Aquariums. The median life expectancy of western lowland gorillas is 32 years. They’re native to the rainforests of Africa’s Congo Basin and are listed as critically endangered with a rapidly diminishing population.