According to a statement, a 59-year-old gorilla named Choomba, who was among the “founding members of the population at Zoo Atlanta” was euthanized on Thursday.

Zoo staff cited “a marked decline in her physical condition due to advanced arthritis and other complications,” as what brought them to the decision to euthanize Choomba. “Given her poor prognosis and with concern for her comfort and quality of life, the teams made the extremely difficult decision to euthanize her,” they added.

Choomba was first brought to Zoo Atlanta in the 1980s, and “her descendants include grandchildren, great-grandchildren, and a great-great grandchild living at accredited zoos around the U.S..”

She spent the last years of her life in a social group with senior male gorilla Ozzie, who according to the zoo is the world’s oldest living male gorilla at 61.

Vice President of Collections and Conservation for Zoo Atlanta, Jennifer Mickelberg, said, “Choomba leaves a tremendous legacy at Zoo Atlanta, in the zoological gorilla population in North America, and in the hearts of those who knew her best.”

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