The Cheetah at TwilightWhat do you do with the world’s fastest mammal when it is too old to run? Or with an ancient fox that walks in circles? If you are a zoo veterinarian, you have some difficult decisions to make.
One day last spring, an elderly cheetah named Togo limped to the concrete lip of his enclosure, paused, then lifted his right front leg as though presenting it. His penny-sized pupils swept over his little kingdom at Roger Williams Park Zoo in Providence, Rhode Island, hinting at an instinct both violent and deadly, yet long dormant. The look was arresting. “He’s a gorgeous animal,” Cheryl Cullion, V90, then the zoo’s head veterinarian, told me with a parent’s pride.
As if responding to the praise, Togo, all 110 regal pounds of sinew and spotted fur—symmetrical black lines streaming from his eyes like tears—stepped down onto the brown grass. Just like that, his limp disappeared. Still, it was hard to imagine him sprinting across an African plain in 20-foot bounds, faster than the Friday traffic that now whizzed behind him on I-95. “He and I have never run,” said his softspoken keeper, Laura Isaacs. “He’s a walker now.”
Indeed, the lame leg contained an Erector Set’s worth of hardware. At 15, Togo had far surpassed the 8 to 10 years cheetahs typically live in the wild. Each day, as he edged closer to the record age for a cheetah in captivity, 18 years, he paced the perimeter of his exhibit, wearing a muddy track around his third of an acre of grass, with its small tree and handful of tire-sized rocks at the center.
In zoos across the country, as animals defy age expectations, such geriatric mini-dramas are becoming commonplace. This year, when the Philadelphia Zoo lost Petal, the country’s oldest African elephant, she was 52. At the New York Aquarium, a sand tiger shark named Bertha lived to an ancient 43. As veterinary medicine and animal husbandry continue to advance, virtually every American zoo will find itself caring for elderly animals—and struggling with a host of challenges.
Modern animal care has solutions for many of the problems advanced age presents: blind animals get brighter lights, animals with kidney failure get dialysis, and toothless animals get soft food. But infirmities are often difficult to spot. By instinct, old animals mask weakness lest they become easy pickings for predators. And even if zookeepers do notice signs of distress, there is often no prescribed treatment when an animal presents an odd symptom. Veterinarians must learn as they go. Consider the case of Kenda, an elderly polar bear at the EcoTarium in Worcester, Massachusetts, who started listing to the left and staring blankly for 30 seconds at a time. Even though Flo Tseng, an assistant professor at Tufts Cummings School of Veterinary Medicine and director of the Wildlife Clinic, cared for the bear for seven years, she still had to observe her carefully and consult with colleagues before she could diagnose a blood clot and treat it with aspirin.
Perhaps most vexing are the dilemmas zoos must confront as animals approach the end of their lives. A few years ago, only hero veterinarians, spurred on by well-heeled pet owners, performed organ transplants and reconstructive surgeries. Now such complex procedures are becoming the norm. But just because vets can perform surgical miracles, does that mean they should? At what point does an intervention merely prolong suffering? No one has developed a mathematical formula for the cost versus quality-of-life calculus.
Togo’s first brush with the frailties of old age came a few summers ago. The cheetah, then 12 years old, started favoring his front left leg, prompting his keepers to call Cullion, his veterinarian. She tranquilized him with a blowgun dart; then she and an assistant rolled him onto a stretcher, wrestling with his gangly legs, which stuck out in all directions, and loaded him into a pickup truck for the three-minute ride up a narrow road behind the elephant and giraffe enclosures to the zoo’s animal hospital.
Inside, with Togo lying on the padded examination table, Cullion performed a routine exam. She worked her hands over the long bones of Togo’s legs, feeling for anything abnormal. She grasped the bones on both sides of the elbow to flex his legs through the full range of motion. The exam and its accompanying x-ray showed no skeletal problems that would account for the limp.
Cullion prescribed a regimen of nonsteroidal anti-inflammatory drugs and glucosamine, a type of joint lube commonly used to treat arthritis in both animals and people. Pharmaceutical companies don’t make medicine specifically for cheetahs—there’s no money in such a niche market—so approved dosing guidelines were nonexistent. Cullion, like zoo vets everywhere, had to calculate an appropriate dosage from the body of knowledge gradually amassing as colleagues report their results.
For a while, the treatment worked. Togo returned to the gray imitation-rock spires in his section of the Plains of Africa exhibit, climbing onto ledges and into shallow caves. He’d pounce on hapless squirrels or mockingbirds, or laze in the shade on muggy summer afternoons. But over the next couple of years, he developed a serious limp that he couldn’t shake. Veterinarians and keepers tried everything short of surgery to help him. In addition to the drugs, he was ordered to rest for a six-day stretch, and zoo workers installed a step to halve the distance from the ground to his four-foot-high perch. Then, in April 2007, when Mike McBride, associate veterinarian at Roger Williams Park Zoo, was examining Togo, he flexed the cat’s right front elbow and heard an ominous click. X-rays confirmed his suspicion: degenerative joint disease in the right elbow and wrist. The arthritis pain from such an ailment would easily explain the limp. Whether Togo’s comfort and quality of life could be restored was questionable.
Thus in the next of their weekly animal management meetings, the zoo’s veterinary and curatorial staffs had a tough decision to make. It wasn’t the only one. Also on the agenda was a discussion of what to do about Chatham, a blind geriatric arctic fox with an affliction that made him unable to empty his bladder, which would swell grotesquely. But no one was ready to give up on either animal.
At Roger Williams Park Zoo, euthanasia is never a foregone conclusion. It’s a last resort to alleviate suffering. Fewer than half the animals there die in this way. Zoo animals, by virtue of their visibility, come to mean many things to many people, and Flo Tseng, with her years of background tending to Kenda, has seen such bonds cement over time. “When these animals get very aged, the public gets very attached to them,” she told me recently. “Kenda is one of the symbols of the EcoTarium and Worcester in general.”
It so happened that Chatham was the one remaining arctic fox at Roger Williams. And Togo, for his part, had endeared himself to the community ever since the day he came to Providence 14 years earlier. He flashed his personality when keepers gave him his weekly bones or deer hides, carrying the prizes in his mouth as he paraded around his enclosure. He’d been the highlight of a summer camp program. The zoo’s annual road race was named the Cheetah Chase 5K.
Despite his limp, Togo prowled actively around his pen. His energy made him what Cullion calls a “good exhibit animal.” He also had a clean medical history, and though he’d surpassed his life expectancy, cheetahs are comparatively long-lived. But his care, unlike Chatham’s, appeared to require extreme measures. It was time to consult a specialist.
The team called Rob McCarthy, V83, an associate clinical professor and veterinary surgeon at the Cummings School, who in the past had performed a tricky joint operation on a gazelle at the zoo. While McCarthy was excited to attempt a procedure that had never been done on a cheetah before, he was surprised that the zoo wanted Togo to go under the knife. To his mind, here was a geriatric zoo animal about to undergo an invasive surgery. Old animals, like old people, have weak bones, which make for extended convalescence. The potential for failure was high, and the post-op level of care would be demanding. But Togo’s keeper was willing, and the others on the team were similarly committed. “The decision from them, God love them, was the cheetah can’t live like this, it can’t be out hobbling around,” McCarthy told me later. “So it was either this or put him down.” The surgery was scheduled.
With enough colorful duffel bags to be “an advertisement for L.L. Bean,” as McCarthy put it, he and his entourage descended upon the animal hospital at Roger Williams Park Zoo on the appointed day in June 2007. The bags’ cheery hues reflected one of the practical realities of veterinary surgery, which is that conditions change faster than it takes to locate a specific box in a dozen identical bags; McCarthy’s color code was for organization. He and his colleagues had come expecting to immobilize Togo’s right front ankle with a curved metal plate, but they were ready for anything.
There were no split-second changes of plan in store this time. At the head of the table where Togo lay with his leg sterilized and shaved to the spotted skin, the monitor flashed consistently reassuring information. Cullion looked on as McCarthy grabbed a scalpel, sliced into Togo’s ankle, and scraped away the cartilage to give the metal a place to grip. He then drilled 20 holes in Togo’s leg and foot bones and affixed the metal plate with screws. After McCarthy had sewn up the incision, Cullion loaded Togo into the pickup truck and climbed in with him for the short ride home. Groggy but in good shape, the cheetah entered six weeks of rehabilitation, with exercise restrictions that made zookeepers bring his fences in close, exiling him to a corner of his exhibit. The staff also removed his perch and tacked up a sign that read: “This animal is under veterinary care.”
Togo progressed to everyone’s satisfaction. After a few days of keeping his repaired leg off the ground, he began to put weight on it. Amazingly, he was soon his old self, sweeping the hay pile off his floor with an insolent paw, whining impatiently for the choice cuts of meat that hid his medicine. It was as if the surgery had taken years off his age. Then, after recovering for less than three months, he came up severely lame again. He walked haltingly, never letting his right front leg touch the ground. Zoo staff made another appeal to McCarthy.
Suspecting that the metal plate had loosened or become infected, McCarthy drove to Providence expecting to remove that piece of hardware. But a pre-op x-ray showed something much different: Togo had broken his right leg. The limb now needed to be rebuilt. McCarthy dug into his rainbow of duffel bags and fished out a second metal plate, which he fastened above the first one. But that presented a tricky problem: with the two plates positioned together, all the force in Togo’s leg would transfer to the small unreinforced spot in the middle. So McCarthy gently pulled the other leg bone apart at the fracture point and threaded a stabilizing metal pin down into the bone’s hollow.
By the time the second surgery was complete, McCarthy had donated five hours of surgical expertise to install 28 pins, two 12-inch metal plates, and a railroad-spike of a pin extending from Togo’s elbow to his wrist. All he could do was confine his patient to rest and hope for the best.
The “best” was what I witnessed when I visited last spring. There were glimpses of Togo’s old magnificence, yes, but plenty of other sights to temper them. As I watched the big cat pace the perimeter of his enclosure, a red-breasted robin alit on the ground in front of him. He approached it without breaking stride, strings of slobber dangling from the corners of his mouth. He took a step; the bird hopped forward. Another step, the bird hopped forward again. Though the cheetah is one of Africa’s fiercest land hunters, fast enough to run down any other animal on earth, this one no longer even scared a songbird.
Zoogoers stop in on such vignettes and snap a few pictures before leaving for the wild dogs in the next enclosure. If they had then headed up to the polar bears on that fine day, they would have passed an empty wooded enclosure that used to house the arctic foxes, Chatham among them. Beginning in February, the animal—blind and sick, the last of several siblings in the fox pen—had shown signs of cognitive dysfunction syndrome, a condition similar to Alzheimer’s that caused him to circle endlessly when he wasn’t eating or sleeping. The zoo had called in a behavioral specialist, who had ordered medication and a special diet. Despite these measures, the circles hadn’t stopped. As Cullion would write in an email to zoo staff, the time had come to “restore Chatham’s dignity and peace.”
So what does euthanasia—literally, “good death”—mean for a zoo animal? In March, it meant a zookeeper scooped up Chatham and cradled him tightly. As Cullion readied the syringe that would deliver the lethal injection, the keeper began to sob. Cullion whispered that it’d be OK. She didn’t know whom she was comforting. She slid in the needle and slowly depressed the plunger. Chatham’s breaths became slower and shallower as he drifted off, and then, he was gone. “With the sun shining brightly and in the arms of one of his keepers,” Cullion wrote to the zoo staff, “Chatham joined his brothers.”
At the time, Cullion hoped Togo would carry on, maybe long enough to make a go at becoming the nation’s oldest cheetah. “I’d like him to live a couple more years at least,” she told me, before adding a knowing caveat: “provided he’s comfortable.”
In May, Togo came up lame for a fourth time. Cullion, Mike McBride, and the zoo’s curators, directors, and animal keepers had one final discussion with McCarthy, who consulted by conference call while he was on vacation in the tropics. The surgical option on the table now was amputation. The assembled experts and caretakers weighed what the six-week healing time would mean for such an old animal. Ultimately, though, they considered what it means to be a cheetah, a creature born to sprint at speeds of up to 70 miles per hour. “The thought of the fastest mammal on earth—amputating his leg to keep him around for another year would be sort of an assault on his dignity,” Cullion said. And with that consensus, Togo was released into the twilight, a few days shy of his Sweet 16.
When an animal dies, the zoo’s veterinarians and the keepers feel the loss, but there are many other needy animals to treat, and zoos owe something to that kid visiting for the first time. Cullion, who since has left Roger Williams Park Zoo and intends to go into private practice, told me she does her best to be dispassionate. “Zoos want to honor what an animal contributed to education, entertainment, and the zoo,” she said. “But the reality is you can’t dwell on it. You definitely have to move on. The upside to the situation is it opens space for another animal.”
With Togo gone, the keepers dismantled one of the fences of his enclosure to give the zoo’s trio of plump and hyperactive wild dogs more space to romp around in. In time, the muddy track that the cheetah wore inside his fence line will fade, and the grass will grow in again.
Sweaty, bearded, and laden with 30 pounds of camping gear, CASEY LYONS first got the notion to write about elderly animals while hiking through a small zoo on the Appalachian Trail. He completed his graduate degree at Columbia University’s Journalism School in May, and now resides in Boulder, Colorado.