Zoo Atlanta euthanized its oldest gorilla, 50-year-old Machi, on September 13 after age-related health problems, including severe chronic osteoarthritis, left her with a poor medical prognosis. The loss comes as the zoo also announced happier news: 27-year-old Lulu is pregnant and expected to give birth during the 2026 holiday season, marking the 27th gorilla born at the facility.
Gorillas are generally considered geriatric after age 40, underscoring just how far Machi had outlived typical expectations for her species. Zoo Atlanta officials say Machi was humanely euthanized because of growing pain and discomfort tied to her advanced age, as reported by WABE. Gina Ferrie, quoted in that report, said mourning senior individuals and anticipating new infants are simply part of life at zoological organizations, adding that Machi was a beloved and extraordinary individual while Lulu will bring new life to the gorilla population.
A Life Rooted In Zoo Atlanta's Founding Generation
Machi was born in 1976 at the Emory National Primate Research Center and arrived at Zoo Atlanta at age 12 alongside her mother, Choomba, the same WABE report notes. The pair joined the original gorilla group when the Ford African Rain Forest opened in 1988, a habitat that marked the zoo's historic shift away from concrete cages and has since hosted 26 gorilla births, according to Zoo Atlanta.
Machi spent time away from Atlanta as well. She lived at Zoo Knoxville from 2013 until March 2021, when she returned to Zoo Atlanta to join a habitat specifically tailored for senior gorillas managing joint stiffness and mobility decline, per WBIR. Zoo Atlanta team members have published more than 100 papers on maternal care, reproduction, social behavior, and cognition drawn from decades of study of gorillas like Machi, the station's report notes.
Machi's Family Tree Runs Through Atlanta History
Machi became the mother of Willie B. Jr., the only son of the late silverback Willie B., and she also bore two offspring with the late gorilla Ozzie. Willie B. himself arrived at Zoo Atlanta in 1961 from Cameroon and spent 27 years in a glass enclosure before finally moving outdoors in 1988, becoming a major Atlanta civic icon until his death in 2000, according to Wikipedia. He was named after former Atlanta Mayor William B. Hartsfield.
Machi's mother, Choomba, was an original founding member of Zoo Atlanta's gorilla program who died at age 59 in January 2022 as the fourth-oldest gorilla in the world, per Zoo Atlanta. Ozzie, who fathered two of Machi's offspring and was a grandfather to Lulu, died that same month at age 61 as the world's oldest known male gorilla, according to the zoo, which also noted Ozzie made history in 2009 as the first gorilla to participate in voluntary blood pressure readings. With Machi's death, Kuchi, a 41-year-old member of the original 1988 group, is now one of the last living links to that founding troop.
Lulu's Pregnancy Brings New Hope
Lulu, born in 1999, is Willie B.'s youngest daughter and Ozzie's granddaughter through her mother, Kuchi. Her pregnancy was confirmed via ultrasound in June, and the coming birth will be her third child, per WABE's reporting. She is a member of the troop led by silverback Taz, a 37-year-old male born and raised at Zoo Atlanta who has sired at least 11 offspring there, according to a Gorilla SSP Facebook post.
Zoo Atlanta's gorilla program operates within the Association of Zoos and Aquariums' Gorilla Species Survival Plan, which cooperatively manages roughly 350 western lowland gorillas across about 50 accredited North American institutions to preserve genetic diversity, as Hoodline has reported. Zoo Atlanta transferred three female gorillas — Andi, Merry, and Anaka, direct descendants of Machi and Choomba — to San Antonio Zoo in November 2025 to help populate its new Congo Falls habitat, part of the same species-wide breeding coordination effort.
Every birth carries outsized weight for the species. Wild western lowland gorilla populations have declined by 60 percent overall, and by as much as 90 percent in parts of western Africa over the past 25 years, due to poaching, habitat destruction, and disease outbreaks like Ebola — a decline that has left the species classified as critically endangered by the IUCN, according to Zoo Atlanta. Lulu's expected infant, due before the end of the year, would become the 27th gorilla born at the zoo since the Ford African Rain Forest opened in 1988.
