Endangered gorilla dies at San Francisco Zoo at age 43

SAN FRANCISCO -  A critically endangered Western lowland gorilla, named "Oscar Jonesy," died on Thursday afternoon following a medical procedure at 43 years old, according to the San Francisco Zoo.

He was the third-oldest male of his species living in a U.S. zoo.

The average lifespan of Western lowland gorillas is 30 to 40 years in the wild.

"We are heartbroken by the loss of Oscar," Zoo CEO Tanya Peterson said in a statement "He was truly an amazing ambassador for this critically endangered species and a favorite among staff, guests and volunteers alike."

Oscar's surgery went well, according to Chief veterinarian Dr. Adrian Mutlow, and he was being monitored during recovery from anesthesia, but despite showing initial signs of recovery, he suddenly became unresponsive and stopped breathing.

Since Oscar had no serious signs of illness, there is no exact cause of death.

The zoo didn't specify what type of medical procedure the gorilla underwetn. 

Oscar Jonesy was born in 1981 and had resided at the Buffalo Zoo for many years before becoming the "silverback" or head of SF Zoo’s critically endangered "troop" in 2004.

SF Zoo's critically endangered Western lowland gorillas live in the Zoo's "Jones Family Gorilla Preserve", an open-air habitat with a window that allows the animal care teams to monitor the troop. 

Oscar's death leaves three female gorillas: Bawang, Monifa and Kimani. 

 A critically endangered Western lowland gorilla, named "Oscar Jonesy," died on Feb. 6, 2025. Photo: SF Zoo/Marianne Hale