The king of the jungle is dead.
JoJo, Brookfield Zoo’s silverback western lowland gorilla, suffered a fatal cardiac arrest Sunday during an emergency procedure. He had been experiencing an acute illness, according to a post from the zoo on Facebook.
The hulking gorilla, who weighed 420 pounds when he moved into the zoo, will no longer gorge himself on banana tree and grape leaves.
“JoJo was very smart and learned new behaviors quickly during husbandry training sessions,” a Brookfield Zoo representative wrote in the post.
“He was known for keeping order in the gorilla group by quickly breaking up squabbles and often showed his gentler and patient side when interacting with his offspring,” it continued.
The 42-year-old gorilla was considered “geriatric,” the zoo wrote. He lived 10 years beyond the typical life span of a male gorilla in managed care.
[ JoJo the gorilla settles in at Brookfield Zoo ]
“We will miss JoJo dearly,” the zoo wrote. A spokesperson from the zoo did not immediately respond to the Tribune’s requests for more information on the gorilla’s death.
JoJo was brought to Brookfield Zoo in 2012 as a part of a breeding program aimed at bolstering his species. He moved into the Tropic World habitat and quickly got to work.
“Let’s just say he hasn’t been hesitant to respond to the females,” zoo primate curator Craig Demitros said when JoJo arrived.
The animal sired three infant gorillas: Nora in 2013, Zachary in 2015, and Ali in 2018.
He fathered two more gorillas before he came to the park, including one at the Lincoln Park Zoo and another at the Louisville Zoo.
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Those kids were consequential: Western lowland gorillas are critically endangered, the World Wildlife Foundation says. The species’ central African native populations have been hit hard by poaching and disease in the last 20 years, the WWF said.
“The loss of JoJo is great, but his legacy will live on in the overall zoo population for this critically endangered species,” according to the post.
JoJo was as popular as he was prolific. Chicagoans responded to the news of JoJo’s passing by posting dozens of their own photos of the lionized gorilla on the zoo’s Facebook page, offering one last glimpse at the awe the animal inspired.
“He was magnificent. I enjoyed countless hours watching him and the others interacting. He was very much a good leader and father to the group,” a Facebook user named Linda Dicintio wrote.
“How incredibly sad,” user Lisa Binetti wrote. “He was such a mesmerizing force!”