Alpha Male Lowland Gorilla Dies At San Francisco Zoo

SAN FRANCISCO — San Francisco Zoo & Gardens is mourning Oscar Jonesy, its beloved 43-year-old lowland gorilla and leader of the zoo's gorilla troop, who died unexpectedly Thursday after a medical procedure.

The western lowland gorilla was the third-oldest male of the critically endangered species living in a U.S. zoo.

"We are heartbroken by the loss of Oscar," Tanya Peterson, the zoo's CEO and executive director, said in a statement. "He was truly an amazing ambassador for this critically endangered species and a favorite among staff, guests and volunteers alike. I thank our incredible animal care teams and the multiple medical specialists who participated to mitigate the risks associated with any medical procedure, especially in an aging great ape.

"We are grateful for the opportunity to have known Oscar and remain awed by his nobility and quiet strength," Peterson said.

The zoo's chief veterinarian, Dr. Adrian Mutlow, said Oscar's procedure went well, and another veterinarian was monitoring him as he recovered from anesthesia when he suddenly became unresponsive and stopped breathing.

"We responded immediately but even with the assistance of critical care specialists from Stanford, we were unable to revive him," Mutlow said. "With no signs of serious illness found during the examination, we do not have a definitive cause of death."

Mutlow said zoo officials should know more after a necropsy examination Friday at the UC Davis School of Veterinary Medicine.

The zoo said the average lifespan of western lowland gorillas in the wild is 30 to 40 years.
Oscar was born in 1981 and lived at the Buffalo Zoo for many years before becoming the alpha male of the San Francisco Zoo's gorilla troop in 2004.

"Oscar was the silverback of the troop," said Dominick Dorsa, the zoo's executive vice president of animal care. "As the troop's leader, he provided a sense of calm and mediated conflict. The females in our troop definitely deferred to him, and we are giving them the opportunity to mourn his passing. We will be monitoring the remaining troop as they go through a mourning period."

The zoo's western lowland gorillas live in the Jones Family Gorilla Preserve, nearly an acre of open-air habitat with a wellness window allowing caretakers to monitor the troop safely. The habitat attempts to replicate a gorilla family's surroundings in the wild as much as possible.

The area is now home to three adult females: Bawang, Monifa and Kimani.

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