The remaining gorillas living at the Cincinnati Zoo will need emotional support following the tragic death of 17-year-old silverback gorilla Harambe on Saturday, according to one animal psychologist.
In an interview with PEOPLE, Dr. Penny Patterson PhD, the co-founder, president and director of research for The Gorilla Foundation, says the gorillas there could face depression following the loss.
In 1972, Patterson began her work with one-year-old Koko, a western lowland gorilla who now uses sign language and flashcards to communicate. She observed the animal suffer from loss more than once and mourn one beloved feline friend for 20 years.
“When she would see a picture of a kitten that looked like All Ball, she would sign ‘cry,’ ‘sad,’” Patterson says. “She also lost a gorilla who was like a brother to her, and she went into a depression. She didn’t talk much, eat much, sleep much. Classic sort of human depression.”
Patterson expects that the remaining Cincinnati Zoo gorillas — there are now ten in all — may respond the same way.
“I would expect that the bond was pretty close and the females might react the same way and will need some emotional support,” she said.
This support comes in the form of speaking openly about the death, Patterson says.
“I would explain the loss if they didn’t see it [happen],” she says. “They understand English. Understanding that he was a great loss to everyone, and that he was a hero. That’s what he was.”
Patterson suggests explaining the situation much like you would to a person. “A close caregiver would be gentle with them, understanding of them, explain [what occurred],” she says. “I talk to them as though they are other persons. We speak to them as if they are other persons because they are, they’re so closely related to us — how could they be anything else? Two percent of DNA is all the difference there is.”
Patterson, who didn’t watch the footage of the 4-year-old in the enclosure with Harambe, for fear “it will affect me and that will affect the gorillas around me,” hopes that the tragedy will help raise awareness of the plight of endangered gorillas.
“They need our help and they need it now,” she tells PEOPLE. “To bring attention to their plight, to their intelligence, to their emotional awareness, their sensitivity, their amazing being — and we just can’t stand the loss, we need them. If we lose them, we lose ourselves and part of ourselves. This is possibly a call to awaken to our kinship with them, actually to our kinship with all life.”