ATLANTA (WSAV) – Zoo Atlanta announced the passing of Choomba, a 59-year-old female western lowland gorilla, on Thursday.

According to Zoo Atlanta, Choomba was the second-oldest gorilla at the zoo and the fourth-oldest gorilla in the world.

Zoo officials say veterinary teams had been monitoring Choomba following a decline in her physical condition due to advanced arthritis and other age-related complications. 

Given her poor prognosis and with concern for her comfort and quality of life, the teams made the decision to euthanize her.

Choomba was one of the founding members of the gorilla population at Zoo Atlanta.

The gorillas arrived at the zoo in the 1980s during the opening of the Ford African Rain Forest exhibit.

Choomba was the mother of Machi, Kudzoo, and Sukari, and the grandmother of Willie B., Jr., Merry Leigh, Anaka, and Mijadala, all of whom live at Zoo Atlanta. 

Choomba’s descendants also include grandchildren, great-grandchildren, and a great-great grandchild living at zoos around the U.S.

A necropsy, or the non-human equivalent of an autopsy, will be performed through the Zoo’s partnership with the University of Georgia Zoo and Exotic Animal Pathology Service in the College of Veterinary Medicine. Preliminary results should be available in several weeks.