Siri had already died twice and nobody would have blamed the malnourished chimp for giving up the fight, but she's good at surprising people.
Siri keeps going, said Jennifer Davis, the zoo's ape supervisor.
“We didn't know if she would recover. We didn't know if she would make it,” she said. “She has such a good little fight in her.”
Siri was born a year ago this week to a 56-year-old chimp named Susie who really wasn't supposed to be pregnant in the first place.
Susie had been on birth control for years; like all chimps in accredited zoos, she was put on birth control for life at age 40. But they took her off it because veterinarians worried that at her old age, her long-term birth control use might put her at a higher risk for heart attack or stroke, said Scott Shoemaker, director of the Sunset Zoo in Manhattan, Kan.
Surely, everyone thought, a chimp that old wouldn't get pregnant.
“Obviously, she got pregnant,” Shoemaker said. “She was not post-reproductive.”
But Susie and her pregnancy were healthy. She gave birth among the other chimpanzees at the zoo, and she cared for and nursed her baby, Siri.
But as the months went by, Siri wasn't growing, Shoemaker said. Zookeepers were worried. They asked other chimp experts for advice.
In April, Siri and Susie were given a battery of tests. It turns out, Susie wasn't producing enough milk, and the milk she was offering Siri didn't have the nutrients that the baby chimp needed.
The first choice would be to leave Siri with her mother, said Steve Ross, chairman of the chimpanzee Species Survival Plan, a nationwide breeding strategy designed to keep the chimp population healthy and genetically diverse.
But Susie couldn't care for Siri, even though she was trying. In human terms, Susie would be about 100 years old, he said.
Siri would need a surrogate mother, a move that happens only once every few years, Ross said.
Three zoos nationwide had chimps that could fill the surrogate role, including Oklahoma City, Ross said. After much discussion and debate, the decision was made to move Siri.
“Oklahoma City really took a big leap forward by saying they would be able to take on this role,” Ross said.
Growing into herself
Siri weighed 3½ pounds when she arrived at the Oklahoma City Zoo on April 20. At 8 months old, Siri weighed as much as a newborn.
“It was really shocking how small she was,” Veterinary Director Jennifer D'Agostino said.
Her wrinkly skin hung on her frame. Her head and eyes looked too big. Her ears stuck out. Her hair was dull and her skin looked ashen. She had deep ridges on her skull.
“There was severe malnutrition,” D'Agostino said. “The brain suffers from that.”
She slept a lot. She couldn't walk or climb or do other things a chimp her age would do.
Seven staff members rotated 8-hour shifts, watching Siri 24 hours a day for weeks on end. A few other zoo workers volunteered for some of the shifts to help out.
Veterinary staff suspected some type of genetic disorder that blood work and X-rays couldn't show. D'Agostino got in touch with a Harvard researcher who could compare Siri's genome to the genetic maps of other, normal chimps.
Surprisingly, Siri's genes are perfectly normal, D'Agostino said.
But she had plenty of challenges.
Zoo officials called on an array of medical experts from throughout the metro to help build her muscles, check her development and encourage her eating.
“Her head started filling out,” said Davis, the ape supervisor. “She grew into normal proportions. It was cool to see.”
It was time for her to meet the other chimps.
That's when she lost her arm.
Siri was introduced to the other chimps through a fence-like mesh.
Kito, a 24-year-old female, was the most interested. Three years ago, Kito had wanted to be a surrogate mother to a chimpanzee named Zoe, when the chimp's mother died suddenly during childbirth. But another female chimp had already bonded with the baby.
So the appearance of Siri was especially exciting. Davis said. Kito sat at the mesh, anxiously adoring the little chimp. They touched and looked at one another. Siri stretched out her arm, and Kito pulled.
“Kito wanted her and just pulled,” Davis said. “Her arm was just so small. It just couldn't take it. Kito did not want that to happen.”
Siri's forearm was destroyed.
Kito retreated out of confusion and fear, Davis said.
Zoo staff whisked her to the zoo's veterinary hospital and called in an orthopedic surgeon.
Then Siri's heart stopped beating. Veterinarians revived her with CPR. Her heart stopped again. She was revived again.
Zoo staff talked about whether it was all too much. If she survived, would it be a life worth living? Would she make it?
“Everybody said, ‘Let's let Siri decide,'” said Davis. “It was amazing that she even came back twice. This chimp really wanted to live.”
Finding a family
Siri's arm was amputated above the elbow successfully, and once again, the chimp surprised everyone around her. She went right back to eating and didn't give her shortened arm a second thought.
Siri grew strong and eventually was ready to go in with other chimps without the fence separation.
Kito — the one who crushed her arm accidentally — took her under her wing immediately. Another adult chimp, Mwami, doted on her, too. Eventually the zoo's young chimp, Zoe, was introduced.
The chimps don't mind her missing arm one bit, Davis said. They play with it, groom it and mouth it. One chimp even shakes it like a hand.
Her adopted mother is especially kind. “Kito is so good about knowing when Siri needs the extra support,” Davis said.
Kito allows Siri to ride high up on her neck, so Siri can use her shorter arm to wrap around her mother's neck.
The other chimps will be introduced one by one, Davis said.
Siri could come out on public display in the next couple of weeks depending on her health and the weather, Davis said.
She's healthy and growing steadily, said D'Agostino, the veterinarian. Vets and keepers still keep a close eye on her to make sure she's going in the right direction.
“I think she'll be normal. She'll just be small,” D'Agostino said. “She's a tough little chimp.”