This month, as the patient lay anesthetized on a table, a cardiologist made a half-inch incision in the skin of his chest. She removed a small implanted heart monitor that had faulty batteries and inserted a new one.
The patient, like many older men, had been diagnosed with heart disease; The monitor would provide continuous heart rate and rhythm data, alerting your doctors to irregularities.
Closing the incision required four careful stitches. In a few hours, the patient, a gorilla named Winston, would reunite his family in his habitat at the San Diego Zoo Safari Park.
“Winston, at 51 years old, is a very old male gorilla,” said Dr. Matt Kinney, senior veterinarian at the San Diego Zoo Wildlife Alliance, who led the medical team through the procedure. Thanks to improved health care, new technologies and better nutrition, “we’re seeing animals live longer, and they’re also healthier longer,” he said.
In “human-managed care” (the term “captive” is no longer used in zoos), gorillas can live two decades beyond the 30 to 40 years that are common in the wild, and longer long as gorillas in zoos. has done so over the past decades.
However, as with their human relatives, aging also brings chronic diseases that require testing, diagnosis and treatment. Gorillas are prone to heart disease, the leading cause of death for them and for us.
So now the questions facing Winston’s caregivers resemble those faced by doctors and older human patients: How much is the treatment too much? What is the trade-off between extended lifespan and quality of life?
Geriatric care of wildlife “has become more and more sophisticated,” said Dr. Paul Calle, chief veterinarian of the Wildlife Conservation Society, based at the Bronx Zoo. “People’s medical and surgical knowledge can be directly applied. »
This is more like human geriatric care. To keep gorillas healthy, zoo veterinarians not only turn to technologies and medications developed for humans, but also consult with medical specialists like cardiologists, radiologists, obstetricians and dentists.
Winston, for example, takes four common heart medications that people also take, but in different doses. (He weighs 451 pounds.) The heart monitor he received, smaller than a USB stick, is also implanted in humans. Winston received his annual flu shot this fall and is undergoing physical therapy for arthritis.
“We’re looking to provide comfort to these animals later in life,” Dr. Kinney said.
It’s expensive: There were nearly 20 doctors, technicians and other staff in the operating room when Winston received his new monitor. But the San Diego Zoo Wildlife Alliance, parent organization of the zoo and safari park, covers Winston’s care through its annual operating budget. Donors and partners compensate for certain additional expenses.
“None of our pets have insurance and they never pay their bills,” Dr. Kinney noted.
Several of Winston’s longtime caregivers, called wildlife protection specialists, have retired. But Winston, who has acquired silverback status with age, stays on the job, managing his “troop” of five gorillas, keeping the peace and intervening in squabbles when necessary.
“He’s such a gentle silverback, an incredibly tolerant father,” said Jim Haigwood, curator of mammals at San Diego Zoo Safari Park. “His youngest daughter, he will always allow her to take food out of her mouth.”
The zoo has twice introduced females with sons into the troop, which in the wild could lead to infanticide. But Winston’s caregivers thought he would accept, and he did.
“He spoke of these evils as if they were his own sons,” Mr. Haigwood said. (Once they became rambunctious adolescents, however, they were resettled in their own habitat, an option that human parents might sometimes envy.)
Winston, a western lowland gorilla from central Africa, arrived at the San Diego Zoo in 1984. He enjoyed good health until 2017, when his caregivers noticed “a general slowdown,” said Dr. Kinney, who arranged Winston’s first echocardiogram.
The test showed only “some subtle changes, nothing alarming,” Dr. Kinney said. Everyone was relieved. Normal aging.
Then in 2021, the entire troop contracts the coronavirus, probably transmitted by a human. As with human patients, age matters.
“Winston was the most seriously affected,” Dr. Kinney said. “He had a cough, quite significant lethargy, lack of appetite.” He started holding on to things while he walked.
After an infusion of monoclonal antibodies, Winston recovered. Now, the entire troop has been vaccinated and strengthened against the virus.
But while Winston was being treated, veterinarians and human doctors conducted other tests that revealed health problems. Winston’s heart had begun to pump less efficiently; this led to a daily regimen of blood pressure and heart medications hidden in his food, as well as the implanted monitor. He also takes ibuprofen and acetaminophen to treat arthritis in his spine, hips and shoulders.
More worrying were a CT scan and biopsy showing a cancerous tumor damaging Winston’s right kidney. This has given rise to a debate about risks and benefits that should inform decisions about invasive treatments for elderly patients, but is often ignored for humans.
“Are we doing surgery?” Dr. Kinney remembers asking himself that question. “The big concern was what would the recovery look like? After considering Winston’s age and life expectancy and determining that the tumor was not growing, “we were comfortable continuing to monitor him,” he said.
For now, “we are at a good balance,” he said. It’s not entirely a medical problem, but it reflects Winston’s ability to lead his troop, including a wife, Kami, with whom he has had “a very devout partnership” for 25 years, Mr. Haigwood said.
Some aspects of healthy aging may be easier to achieve for zoo primates than for humans; their guardians only offer healthy choices. “They don’t smoke,” said Marietta Danforth, the director of Heart of the Great Apes Project, a research effort at the Detroit Zoo. “They don’t eat cheeseburgers.”
Winston’s vegetarian diet consists mainly of tree branches and root vegetables. The half-acre gorilla forest where he lives, with its hills, ponds and climbing structures, encourages exercise.
Yet geriatric care necessarily involves end-of-life decisions. Winston could die a natural death one day like Ozziea gorilla who died at the Atlanta Zoo two years ago at age 61, or Colowho was 60 years old when she died at the Columbus Zoo in Ohio in 2017.
But if his quality of life declines, if he stops interacting with the troop and his caregivers, or begins to suffer, the parallels with human care end. Even in California, with its law on medical assistance in dying, euthanasia remains illegal for humans. This is an option for Winston.
“It’s a privilege in veterinary medicine,” Dr. Kinney said. “It also comes with great responsibility.”
If Winston’s doctors, specialists and caregivers conclude, after lengthy discussions, that a painless death would be preferable to a diminished life, “it’s a very calm process,” Dr. Kinney said. After an overdose of anesthesia, he says, “within minutes, there is cardiopulmonary arrest.”
About 350 gorillas — and 930 great apes in total, including bonobos, orangutans and chimpanzees — live in U.S. zoos, Dr. Danforth said. No matter how well cared for they are, some animal rights activists and primatologists say they have no place in zoos.
But even the group People for the Ethical Treatment of Animals, whose position is that wild animals have a place in nature, acknowledged in an email that zoos like San Diego’s, accredited by the Association of Zoos and aquariums, meet high standards of animal care.
Winston “had some great years,” Dr. Kinney said. The gorilla has also become a popular media personality. San Diego will mourn its loss, when and how it happens.
For now, “we want to make sure that Winston is living a good life, that he’s fulfilled,” Dr. Kinney said. “We understand well what makes Winston Winston.”