Brookfield Zoo announced Monday that Ben, a 44-year-old Bornean orangutan, was euthanized Sunday after his health deteriorated rapidly in the last week.
The orangutan arrived at the zoo in 1992 on a breeding recommendation, according to the announcement. Ben was the second-oldest Bornean orangutan in the accredited North American zoo population, the zoo said.
The Bornean orangutan population, which is critically endangered, declined by more than 60% between 1950 and 2010, according to the International Union for Conservation of Nature. A 22% decrease was projected from 2010 through 2025.
According to the conservation union, Bornean orangutan populations are declining as the forests they live in are turned into oil palm, rubber or paper plantations, and others are hunted and killed by humans.
Ben and his mate, Sophia, had four offspring. Two of them, Kekasih and Heidi, still live at Brookfield Zoo. The orangutan also had four grandchildren and one great-grandchild.
His death comes after a long history of heart disease that had been managed with medication for over a decade. In 2018, Ben had to undergo emergency surgery for a ruptured appendix but recovered soon after.
Ben was also being treated for severe arthritis and spinal degeneration for the past several years, the zoo said. Medication initially alleviated his symptoms, but his condition deteriorated in the last week, which made surgery not an option.
Veterinary staff was no longer able to ease the orangutan’s pain, so animal health and care teams made the decision to euthanize him.
“Ben was such a gentle ape and an incredible father. He could often be seen interacting and playing with his offspring,” said Tim Snyder, vice president of animal care. “Additionally, he had a very trusting relationship with his animal care specialists, and voluntarily participated in training sessions and his own health care. He will be greatly missed by the staff and the millions of guests who visited him.”