CHICAGO — Lincoln Park Zoo's last chimpanzee to be born in the wild, Vicky, died at age 50.
Vicky, born in Africa in 1964 and brought to the zoo in 1971, was euthanized following complications "that arose due to her advanced age and long-term heart condition," according to a statement from the zoo.
She was the zoo's oldest chimpanzee. If her age was converted to human years, she would have been in her 90s, the zoo said.
Stephen Ross, director of the Lester E. Fischer Center for the Study and Conservation of Apes at the zoo, said Vicky was good at building nests, climbing and interacting with apes and humans.
"At she zoo she was always very interested in what people were doing, what people were wearing," Ross said. "So, she had that nice ability to go back and forth from the chimp world to the human world. I thought she did a really excellent job showing how complex and how gentle chimpanzees can be."
The zoo is still deciding how it will memorialize Vicky, Ross said. When Keo, her partner, died, he was honored with a memorial webpage where visitors could leave comments expressing their condolences.
"Beyond impacting countless visitors, caregivers and friends of the zoo, Vicky’s passing highlights how much zoos have changed since her arrival. She was the last wild-born ape at Lincoln Park Zoo, offering a link to a practice that no longer takes place," according to the statement.
"Ultimately, the arc of Vicky’s life reminds us of how far zoos have come in planning populations — and offering care. Veterinary advancements have geriatric animals living longer, healthier lives than ever before.
"That doesn’t make it easier to say goodbye to Vicky, but it does offer comfort to all those who will miss her."
Vicky and her partner, Keo, participated in touch-screen computer exercises with other chimps. The exercises tested their intelligence and cognitive skills and were part of research that aimed to better communicate with the animals on their food, activity and other preferences. While she wasn't a "star student," Ross said she did try at the exercises.
Vicky spent the last few years of her life behind the scenes at the zoo, living in an off-exhibit area with her daughters, Magadi and Kibali, and another female chimpanzee named Cookie.
The median life expectancy for female chimpanzees is 38.7 years, according to the zoo.
Keo, the oldest male chimp in North America, died last year at 55.
Here is a 2013 video of Vicky and Keo celebrating their birthdays.