Zoomba's generations of descendants live in zoos across the country.
CNN  — 

Choomba, “one of the founding members of the gorilla population at Zoo Atlanta,” was euthanized Thursday at 59, the zoo announced on its website.

Veterinary staff “had been monitoring Choomba closely in recent days following a marked decline in her physical condition due to advanced arthritis and other age-related complications,” said a zoo statement.

“Given her poor prognosis and with concern for her comfort and quality of life, the teams made the extremely difficult decision to euthanize her,” the statement said.

Choomba arrived at Zoo Atlanta in the 1980s and was the matriarch of four generations of gorillas, said the zoo statement.

Choomba was the mother of Machi, Kudzoo, and Sukari; all still live at the zoo. But “her descendants include grandchildren, great-grandchildren, and a great-great grandchild living at accredited zoos around the U.S.,” said the statement.

“Choomba had been living in a senior social group with Ozzie, who at age 61 is the world’s oldest living male gorilla,” said the zoo.

“This is an extremely difficult day for Zoo Atlanta and most particularly for Choomba’s care team, who knew her intimately and saw and cared for her daily with the greatest dedication,” said Jennifer Mickelberg, PhD, Vice President of Collections and Conservation for the zoo.

“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,” said Mickelberg.