DALLAS (CBSDFW.COM) – The Dallas Zoo’s oldest male chimpanzee Doyle passed away due to age-related health issues, the zoo said Tuesday.

At 49 years old, Doyle was one of the oldest chimps in the Association of Zoos and Aquariums.

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Missy is still the oldest troop member, at age 54.

Doyle the chimpanzee passed away (courtesy: Dallas Zoo)

The zoo said the chimps were all given time to say goodbye to Doyle, who was known as the peacemaker of the troop.

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Doyle came to the Dallas Zoo in 2009 and quickly became a favorite, both by his fellow chimps and humans, the zoo said. He was kind, gentle and generous to all the chimps.

“He was always ready to lend a hand of friendship to anyone who needed it and never held a grudge. He was often a mediator, a comforter, a babysitter and a playmate. He contributed greatly to his endangered species, rearing 11 offspring in his lifetime,” the zoo said in a statement.

The zoo said the other chimps are doing well, but zoo staff will continue to keep a close eye on them for now.

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“Please send your love and support to Doyle’s amazing zoologists who are very close to the animals they care for. This sweet old fella will be deeply missed,” the zoo said.