A very smart orangutan dies captive in zoo

Zoo Atlanta reports that Chantek the orangutan died Monday at age 39 in his enclosure in the US state of Georgia. Pending a postmortem, the cause of death remains unknown.

"He had such a unique and engaging personality and special ways of relating to and communicating with those who knew him best," said Hayley Murphy, the vice president of Zoo Atlanta's animal divisions.

The zoo reports that since 2016 veterinarians had treated him for progressive heart disease, a leading cause of death for great apes in captivity. Prior to his death and without narcosis, Chantek had "voluntarily" gone an echocardiogram to examine his heart's electrical rhythms.

Because of his heart condition, Zoo Atlanta had placed Chantek on a low-sodium diet. In the wild in their native Sumatra and Borneo, where they are known as "the old man of the forest," orangutans mostly feast on abundant fresh fruits such as figs, mangosteens and lychees and apparently experience no such cardioconditions. However, deforestation and other forms of human encroachment have placed both regional species of orangutan on the critically endangered list.

'He was shy'

Born in 1977 at Atlanta's Yerkes National Primate Research Center, Chantek was sent to University of Tennessee-Chattanooga, where anthropologist Lyn Miles raised him in a trailer. She taught Chantek 150 words of American Sign Language. Chantek could use a toilet and clean his room; he worked for an allowance of steel washers, and knew the route to the local Dairy Queen.

When Chantek escaped his confinement after nine years, the university sent him back to Yerkes. He spent 11 years in a 5 foot-by-5 foot (1.5x1.5-meter) cage, where he exhibited clear signs of depression and grew heavy with inactivity. He arrived to Zoo Atlanta in a cage in 1997, at the age of 19.

According to Zoo Atlanta, Chantek "was shy about signing with individuals he did not know and often chose forms of communication which are more typical of orangutans, such as vocalizations and unique hand gestures." He became "one of the oldest living male orangutans" in captivity in North America. Zoo Atlanta reported that Chantek died in a "naturalistic" environment.

Chantek became famous late in life, following the 2014 airing of "The Ape Who Went to College," an episode of the "My Wild Affair" series on the US public broadcaster PBS. Apes who acquired the language of gesture to communicate with their human captors include the 46-year-old gorilla Koko, who lives in a trailer in California, and Washoe, a female chimpanzee who was 42 when she died at a research facility in the state of Washington in 2007.

In 2015, a baby orangutan was born to much fanfare at Berlin's zoo. 

mkg/msh (Reuters, AFP, AP)