This month, as the patient lay anesthetized on a table, a cardiologist made a half-inch incision in the skin of his chest. He removed a small implanted heart monitor with faulty batteries and inserted a new one.
The patient, like many older men, had been diagnosed with heart disease; The monitor would provide continuous data on heart rate and rhythm, alerting your doctors to irregularities.
Closing the incision required four clean stitches. In a few hours, the patient, a gorilla named Winston, would join his family in his habitat at the San Diego Zoo Safari Park.
“Winston, 51, is a very old male gorilla,” said Dr. Matt Kinney, senior veterinarian for the San Diego Zoo Wildlife Alliance, who led the medical team during the procedure. With better healthcare, new technologies and better nutrition, “we see animals living longer and also being healthier for longer,” he said.
In “human-managed care” (the term “captive” is no longer used in zoos), gorillas can live two decades longer than the 30 to 40 years that are common in the wild, and longer than wild gorillas. the zoos. it did in past decades.
However, as with their human relatives, aging also brings with it chronic diseases that require testing, diagnosis and treatment. Gorillas are prone to heart disease, the leading cause of death for them and us.
So now the questions for Winston’s caregivers resemble those faced by doctors and older human patients: How much treatment is too much? What is the balance between prolonged life and quality of life?
Geriatric wildlife care “has become increasingly sophisticated,” said Dr. Paul Calle, chief veterinarian at the Wildlife Conservation Society, based at the Bronx Zoo. “People’s medical and surgical knowledge can be directly applied.”
It 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 such as cardiologists, radiologists, obstetricians and dentists.
Winston, for example, takes four common heart medications that people also take, although in different doses. (He weighs 451 pounds). The heart monitor he received, smaller than a flash drive, is also implanted in humans. Winston received his annual flu shot this fall and is receiving physical therapy for arthritis.
“We are looking to provide comfort to these animals in the future,” Dr. Kinney said.
That’s not cheap: 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, the zoo and safari park’s parent organization, covers Winston’s care through its annual operating budget. Donors and partners offset some additional costs.
“None of our animals have insurance and they never pay their bills,” Dr. Kinney said.
Several of Winston’s longtime caretakers, called wildlife care specialists, have retired. But Winston, who has achieved silverback status with age, is still on the job, managing his “troop” of five gorillas, keeping the peace and intervening in disputes when necessary.
“He’s such a gentle silverback, an incredibly tolerant father,” said Jim Haigwood, curator of mammals at the San Diego Zoo Safari Park. “His youngest daughter will still allow him to take food out of his mouth.”
The zoo has twice introduced females with children to the herd, which in the wild could lead to infanticide. But Winston’s caregivers believed he would accept, and he did.
“He raised those boys as if they were his own sons,” Haigwood said. (Once they became rambunctious teenagers, however, they were relocated to their own habitat, an option that human parents might sometimes envy.)
Winston, a western lowland gorilla native to Central Africa, arrived at the San Diego Zoo in 1984. He enjoyed solid health until 2017, when his keepers noticed “a general slowdown,” said Dr. Kinney, who organized the first echocardiogram. by Winston.
The test showed only “a couple of subtle changes, nothing alarming,” Dr. Kinney said. Everyone felt relieved. Normal aging.
Then, in 2021, the entire troop contracted the coronavirus, likely transmitted by a human. As with human patients, age mattered.
“Winston was the most severely affected,” Dr. Kinney said. “He had a cough, quite significant lethargy and lack of appetite.” He began to grab onto objects as he walked.
After an infusion of monoclonal antibodies, Winston recovered. Now all the troops have been vaccinated and reinforced against the virus.
But while Winston was being treated, veterinarians and human doctors performed other tests that found health problems. Winston’s heart had begun to pump less efficiently; That led to a daily regimen of blood pressure and heart medications hidden in his food, and the implanted monitor. He also takes ibuprofen and acetaminophen for arthritis in his spine, hips and shoulders.
More concerning was a CT scan and biopsy that showed a cancerous tumor damaging Winston’s right kidney. That sparked the kind of risk-versus-benefit conversation that should inform decisions about invasive treatment for older patients but is often omitted for humans.
“Do we do a surgical procedure?” Dr. Kinney remembered wondering. “The big concern was what the recovery would look like.” After considering Winston’s age and life expectancy, and determining that the tumor was not growing, “we felt comfortable with continuing to monitor him,” he said.
For now, “we are in a good balance,” he said. This is not entirely a medical issue, but it reflects Winston’s ability to lead his troops, including a woman, Kami, with whom he has had “a very devoted association” for 25 years, Haigwood said.
Some aspects of healthy aging may be easier for zoo primates than for people; Their caregivers only offer healthy options. “They don’t smoke,” said Marietta Danforth, director of the Great Ape Heart Project, a research effort at the Detroit Zoo. “They’re not eating cheeseburgers.”
Winston’s vegetarian diet consists mainly of tree branches and tubers. The half-acre gorilla forest where she lives, with its hills, ponds and climbing structures, promotes exercise.
Still, geriatric care necessarily involves end-of-life decisions. Winston could die a natural death someday like Ozziea gorilla who died at Zoo Atlanta two years ago at age 61, or Colowho was 60 years old when he died at the Columbus Zoo in Ohio in 2017.
But if his quality of life decreases, if he stops interacting with the troops and their caregivers or begins to suffer, the parallel with human care ends. Even in California, with its medical aid in dying law, euthanasia remains illegal for human beings. It’s an option for Winston.
“It’s a privilege in veterinary medicine,” Dr. Kinney said. “It also comes with a lot of responsibility.”
If Winston’s doctors, specialists and caregivers conclude, after extensive discussion, that a painless death would be preferable to a diminished life, “it’s a very smooth process,” Dr. Kinney said. After an anesthesia overdose, he said, “within minutes, cardiopulmonary arrest occurs.”
About 350 gorillas (and 930 great apes total, including bonobos, orangutans and chimpanzees) live in U.S. zoos, Dr. Danforth said. No matter how well cared for they are, some primatologists and animal rights activists argue that they should not be kept in zoos.
But even People for the Ethical Treatment of Animals, whose position is that wild animals belong in the wild, acknowledged in an email that zoos like the one in San Diego, accredited by the Association of Zoos and Aquariums, meet high standards of animal care.
Winston “has had some great quality years,” Dr. Kinney said. The gorilla has also become a beloved media personality. San Diego will mourn the loss of him, whenever and however it happens.
For now, “we want to make sure Winston is living a good life, that he feels fulfilled,” Dr. Kinney said. “We have a good understanding of what makes Winston, Winston.”