Gorilla Shot in Cincinnati Zoo Would Have Killed Boy Without Intervention, Expert Says

Days after a 450 pound gorilla named Harambe was shot and killed to protect the life of a 4-year-old boy who fell into his enclosure at the Cincinnati Zoo, Jack Hanna, the Director Emeritus of the Columbus Zoo in Ohio, and the host of a series of television shows about wild animals, defended the decision to put down the animal.

"I’ve seen him take a green coconut, which you can’t bust open with a sledgehammer and squish it like this," Hanna told "Good Morning America" about Harambe, gesturing with his hand the ease with which gorillas can crush fruit. "You’re dealing with either human life or animal life here. So what is the decision? I think it’s very simple to figure that out."

A witness told ABC News that the gorilla was protecting the boy, who ultimately survived the encounter.

"The little boy, once he fell, I don't think the gorilla even knew that he was in there until he heard him splashing in the water," witness Brittany Nicely told ABC News on Sunday, explaining that zoogoers' screams drew more attention to the Saturday afternoon incident.

"The gorilla rushed the boy, but did not hit the boy," Nicely said. "He almost was guarding the boy, was protecting him."

Zoo Witness: Gorilla Was Protecting Boy, Not Hurting Him

Hanna argued that the boy would have been killed were it not for the intervention of the zoo employee who shot Harambe.

"I can tell you now, that there’s no doubt in my mind the child would not be here today if they hadn’t made that decision," Hanna said.

The death of Harambe has reignited a debate about zoos and their purpose. PETA, one of the world's most visible animal rights organizations, released a sharply-worded statement on its website condemning the death of Harambe, arguing that zoos fail to provide an adequate home for the "complex needs" of wild animals.

Four-Year-Old Who Fell into Gorilla Enclosure Expected to Recover

"Gorillas are self-aware. They love, laugh, sing, play, and grieve. Western lowland gorillas are gentle animals. They don’t attack unless they’re provoked," PETA said in its statement.

Hanna defended zoos, noting that they invest money in animal preservation.

"Remember something, no one loves gorillas more than the Columbus Zoo, the Cincinnati Zoo and the zoo world," Hanna said. "We have given literally millions and millions of dollars to preserve these animals, both mountain gorillas and lowland gorillas."