The Los Angeles Zoo announced Friday the death of a 31-year-old male orangutan.
The primate, known as Minyak, died Thursday of cardiac and respiratory arrest. The orangutan suffered since infancy from a chronic respiratory illness known as air sacculitis.
Minyak was undergoing a routine check-up when he died.
Minyak came to the zoo in December 2001 from Yerkes Primate Center in Atlanta. It was believed Southern California's drier climate would help him live longer.
The primate's health improved for a short time after arriving in L.A. but declined again within two years. Minyak underwent a groundbreaking surgery in 2003 to remove the air sac that was causing the health problem. Zoo veterinarians and staff put Minyak through rigorous training and a medication regiment.
After recovering, Minyak was returned to the Red Ape Rain Forest exihibit. He went on to father two female baby orangutans.
"With all of his medical issues, Minyak's zookeepers described him as a fighter, extremely cooperative and very forgiving," a statement from the zoo said. "He will be missed by everyone."
Orangutans once roamed much of Southeast Asia, but are now confined in the wild to the islands of Borneo and Sumatra. The animals can live as long as 35 years in the wild and 60 years in captivity, according to the Smithsonian National Zoological Park.