A chimpanzee who once survived an escape bid in which her partner was shot dead has managed to reach the age of 50.
Koko, who lives at Whipsnade Zoo in Dunstable, has outlived the average life expectancy of a chimp by 10 years.
Before hitting the milestone on Sunday, Koko was famous for her brief escape bid which came in 2007 just after she moved to the Bedfordshire zoo.
Koko was swiftly recaptured and led back to the enclosure but her fellow escapee Johnnie was shot dead because he posed a danger to the public.
Chimpanzees in captivity generally live to around 33 years of age, but they have been known to survive long into their 60s.
Koko was born at Dudley Zoo in the West Midlands in 1973 and moved to London Zoo when she was nine before being transferred to Whipsnade in 2006.
Whipsnade Zoo primate keeper Grant Timberlake said: “Koko might have just turned 50 but she’s still in brilliant health, thanks to the dedicated care of our zookeepers and veterinary team.
“Particularly when she sees her favourite food, it’s like she’s 20 years young again – climbing and swinging as fast as she can through the trees to reach it."
The zoo said Koko suffered from mild arthritis in her hands, which was soothed by low level laser treatments to keep her “pain-free and fully mobile”.
Mr Timberlake added: “Koko herself has contributed to several important conservation projects for her species, helping to improve and protect the health of chimpanzees around the world.”
Vets have carried out ultrasound examinations on her heart, in order to understand more fully the issue of cardiovascular disease in great apes.
Koko’s milestone makes her one of the oldest chimpanzees in Europe.
The current living record holder for Europe, called Coco, celebrated her 58th birthday at Twycross Zoo in Leicestershire in April.
The oldest chimpanzee on record was Little Mama, who was thought to be in her late 70s when she died at a safari park in Florida in 2017.
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