No more monkey business? US mulls pet primate ban

Introduction of federal bill coincides with similar legislative action in UK

June 8, 2021 (published)
By Ross Kelly

Born Free USA photo
Betsy, a baboon, is one of 20 former pets living at Born Free USA sanctuary in Texas. She arrived in 2017 at the reported age of 34, given up by an owner who kept her illegally and who took her to church regularly, as well as Bible school camp and a rodeo, according to Born Free USA spokesperson Karen Lauria. At the sanctuary, Betsy has a best friend, Bruce, also a baboon, and enjoys snuggling stuffed animals and lying on blankets, Lauria said.

They may be prone to unexpected bursts of aggression, harbor a host of diseases and have a penchant for peeing everywhere to mark territory. But those drawbacks haven't deterred thousands of people in the United States alone from keeping nonhuman primates as pets.

Many of the owners are ignorant of the extent of safety risks to themselves, as well as of the animals' complex dietary, housing and social needs, veterinarians lament.

"We have a lot of crazy primate stories," said Dr. Darryl Heard, who treats exotic animals in Florida. He recalls one particularly concerning case involving a client who was a pediatrician.

The client had purchased a capuchin monkey for children at her practice to cuddle and play with. She also took the monkey home to entertain her own infant child. Colloquially known as "organ grinder" monkeys, capuchins are deceptively strong for their size and can cause serious injury to people, as well as carry disease.

"Despite her medical training, she still wasn't aware of the danger to the clients' kids and her own kid," Heard said.

An associate professor at the University of Florida College of Veterinary Medicine, Heard treats nonhuman primates at the college's hospital. Some of his patients are residents of zoos and sanctuaries, but many are private pets. Finding a veterinarian with the skills and willingness to tend to pet primates isn't always easy, he said. Some of Heard's clients travel a long distance, including one who drives across the country from Arizona to receive care for a capuchin.

In brief

Soon, Heard could be seeing fewer such clients, and that wouldn't trouble him: He is among veterinarians who welcome moves by lawmakers on both sides of the Atlantic to ban laypeople from keeping primates as pets.

On May 12, three U.S. lawmakers — two Democrats and one Republican — introduced to Congress the Captive Primate Safety Act, which would ban the sale, transportation and private possession of nonhuman primates.

Coincidentally on the same day, the United Kingdom introduced a raft of proposed rule changes pertaining to animal welfare that include a proposed ban on pet primates. As it stands now, anyone in the U.K. is free to keep them, although owners of certain species considered more dangerous to humans, such as chimpanzees, need to prove they can house them securely.

In the U.S., the ownership of primates, or certain species of primate, already is banned in 31 states. Among the rest, some, such as Florida, mandate a license for ownership; others, such as Alabama, Nevada and Texas, allow ownership of at least some types of primate without a license.

Versions of the Capital Primate Safety Act have been proposed in the U.S. before: Most significantly, one passed the House in 2008 but never got a vote in the Senate. The new bill exempts zoos, research labs, sanctuaries and universities. It would "grandfather" current owners, meaning they could keep their pet primates so long as they register the animals.

In the U.K., keepers able to meet welfare standards akin to those of licensed zoos will be allowed to continue to possess primates under a new licensing regime, subject to conditions and inspections.

Dr. Peter Kettlewell, a veterinarian who treats monkeys in Chipping Norton, England, supports the clampdowns. "Most vets that know anything about primates think keeping them as pets is a bad idea," he said. "Some don't want to go for an outright ban because they're a bit more liberal-minded, but I think everyone recognizes that primates have really complex needs, which are very rarely met by private individuals."

Keeping primates: the hard facts

Precisely, or even roughly, how many nonhuman primates are kept as pets, either globally or in individual countries, is hard to measure because owners typically aren't required to register their animals.

Conservative estimates suggest there are at least 15,000 primates kept as pets in the U.S., according to the nonprofit Animal Welfare Institute.

In the U.K., a government-commissioned study published in December called estimates "highly uncertain," and put the number in the country somewhere between 1,000 and 5,000, based on figures provided by charities, sanctuaries and veterinarians.

Born Free USA photo
Gilbert, a long-tailed macaque, is another sanctuary resident. According to Born Free USA spokesperson Lauria, Gilbert was kept illegally as a pet in New York. Upon sexual maturity, he bit his owner and was given up. Gilbert arrived at the sanctuary emaciated, weak and balding on his lower legs and tail from obsessive grooming, a sign of prolonged stress. Now he is one of the friendliest and chattiest monkeys in the bunch.

Smaller species of primate are typically favored as pets because they are easier to cage and transport; marmosets, tamarins, rhesus macaques, spider monkeys and capuchins are popular types. However, Heard said his practice in Florida sees larger pet primates, too, such as chimpanzees, and unusual species, such as Japanese macaques (snow monkeys). "You can buy anything in the U.S. if you've got enough money," he said.

Heard, who also is a consultant for the Veterinary Information Network — an online community for the profession and parent of the VIN News Service — recalls colleagues treating a pair of chimpanzees that an elderly lady had purchased some 30 years prior. She kept them in a small cage in her backyard — the door had to be ripped off its hinges for the veterinarians to gain access. At the other end of the extreme in housing, Heard said, "There are some other people I've seen that keep their monkeys in their house and actually sleep with them, which is unhygienic."

Small monkeys, and not just capuchins, might bite and scratch. Even meeker primates, such as marmosets and tamarins, can draw blood and require stitches. A bite or scratch from any species of monkey also is a means of transmitting infections. For example, herpes B, harbored by some macaque species, can be deadly to humans.

Still, veterinarians maintain that people present just as big a risk to the health of pet primates than the other way around. "The vast majority of problems we see in captive primates — and honestly, most captive exotics — are husbandry-related," Kettlewell explained. "They're basically caused by us not looking after them properly."

Nonhuman primates, like humans, have complex dietary needs. Moreover, the many species of primates that hail from subtropical climates need warm temperatures and plenty of access to light.

"People think monkeys just need fruits, so we see a lot of malnutrition," Heard said. "You will get a lot of issues with metabolic bone disease from a lack of calcium or vitamin D deficiency." Some primates develop obesity or diabetes because their owners share their own bad eating habits with their pets. "So they're giving them hamburgers and stuff like that," Heard said.

The Simian Society of America, a resource for private owners that includes veterinarians and primatologists among members, recommends a foraging mix that contains dozens of ingredients, such as rolled oats, dry beans, red winter wheat berries, various nuts, unsweetened coconut, vegetable pasta and chopped dates.

Disease transfer, meanwhile, is a two-way street: Nonhuman primates are susceptible to many pathogens that infect humans, such as the viruses that cause measles, influenza and COVID-19, to name just a few. And, like humans, nonhuman primates are complex social creatures that can develop behavioral problems if they are denied constant stimulation.

Marmosets and tamarins, for instance, can form strong monogamous bonds, and juveniles often will stay with their parents for years in the wild. "Just imagine if you as a human got grabbed and stuck in a cage," Heard said. "Basically, you're imprisoned by yourself and you've got some giant that's interacting with you."

Is there room for exceptions?

Some veterinarians accept that private pet owners, in certain circumstances, can provide adequate levels of care. Some fear that blanket ownership bans could drive the trading of monkeys underground.

Dr. Sergio Silvetti, who treats exotics in Birmingham, England, opposes strict prohibitions for those reasons. "Banning anything will push forward the black market, reducing even further the care for these animals," he said.

Silvetti acknowledges that caring for primates is challenging but posits the same could be said for other types of pets. "Horses should live in [herds] but they are kept in little stables; rabbits should live in large colonies; and parrots, in large flocks," he said. Silvetti would prefer to see mandatory licensing protocols introduced for owners. "This will limit the purchase of these animals only to a very small elite of people, and promote high standards of care without a need for the word 'ban,' " he said.

For his part, Kettlewell, who also is senior vice president of the British Veterinary Zoological Society, isn't convinced black-market fears should prevent the introduction of stricter rules. "You can use that argument to stop any law," he said. "If people are hell-bent on breaking the law, they'll break the law. But at least there's a law to break."

To be sure, he has seen clients with a high level of knowledge of primate needs that provide a superior standard of care. Consequently, Kettlewell supports the U.K. government's decision to provide an exception to its ban for owners meeting the same care standards as zoos.

Not all veterinarians in the U.S. like the idea of outright bans, either. Dr. Steven Garner, one of the few practitioners who treats primates in Houston, has seen terrible examples of animal abuse and neglect in his 38 years of practice. "In general, we do not recommend the ownership of any exotic animals, with primates at the top of the list," he said. Still, Garner sees that primates, with their relatively high levels of intelligence, can form particularly strong bonds with humans. He recounts the case of a 35-year old spider monkey that died of congestive heart failure, causing deep distress to three generations of its human family.

"I do see mutual benefits to both the humans and the primates from the right kind of ownership relationship," Garner said. "Primates should enjoy human companionship, as should dedicated humans enjoy nonhuman primate companionship."

Common illnesses and injuries that Garner sees in his primate patients are gastrointestinal problems and trauma from swinging on cabinet doors, causing broken bones in the fingers, hands and tails. Overall, though, he said most of his patient stories aren't nightmares. "I have monkeys who have been well trained to hold their arm out for blood draw," he said. "Just like kids, their behavior is more created by their environment, and there are good primate pet parents and bad ones. The good ones are a pleasure to work with, and the bad ones should have their primates taken away."

Garner, too, fears that outlawing ownership across the U.S. could create a barrier to adequate veterinary care. "If there were a law, it should mandate education about the primates' care, and licensure of those committed to this care," he said.

Anyone considering providing such a high standard of care should expect a hefty bill. The U.K. paper includes a rough estimate of keeping costs that were provided by an accredited U.K. zoo. The estimate comes to £128.74 (US$182.28) per week and includes items like pellets, live food (such as insects), lighting, heating, staffing and cleaning products. Owners must be prepared to bear those costs for at least a decade: Nonhuman primate lifespans range from 12 years for common marmosets to 21 years for squirrel monkeys, 40 years for capuchins and 50 years for chimpanzees, according to the report.

Moreover, nonhuman primates won't necessarily mature as they age in the same way humans do, according to the Simian Society of America. "A monkey is like caring for a 2-year-old human child for the rest of your life," it warns on its website. "You must watch your monkey every second it's free of its cage. They can turn on faucets, unscrew light bulbs, open bottles of nail polish, break your lamps and shred your curtains."

Initial outlays to buy the animals, either from breeders or other owners, can be wide-ranging but generally are steep. According to the British paper, common marmosets can cost from £400 to £1,500 (US$566 to $2,124), while capuchins can cost £250 (US$354) all the way up to £7,000 (US$9,912). "Figures for primates other than common marmosets are less reliable due to comparatively small numbers being sold and the high probability of scam adverts … in particular, in the case of capuchins," the U.K. paper says.

In the U.S., Heard said he knows of marmosets and tamarins costing around $2,500 to $3,000 (£1,766 to £2,119) each, and baby chimpanzees going for upwards of $50,000 (£35,314) apiece. Most buyers, he and others agree, are in for more than they bargained for.

"Some people will have them behaving like a friend living in the home," Kettlewell said. "But at the end of the day, they're wild animals. And we should respect their needs."

This story has been changed from the original to fix an incorrect word attributed to Dr. Sergio Silvetti.

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