By Dr. Becker
A study conducted by researchers at the Fisher Center for the Study and Conservation of Apes at Lincoln Park Zoo has concluded that chimpanzees removed from their mothers as infants develop behavioral and social problems as they mature.
The study involved 60 chimpanzees, 36 of which were taken from their mothers early in life and raised by humans as pets or performers. The results were published in September 2014 in the online journal PeerJ.1
Chimps Raised by Humans Are Socially Stunted
The research team spent over a year observing the chimps, which were living in a variety of accredited zoos and sanctuaries. They learned that the animals raised by humans with little interaction with other chimps during their first four years were less socially competent as adults.
They engaged in less social grooming – a critically important behavior for social bonding in chimpanzees – with their group mates. As Dr. Steve Ross, director of the Fisher Center and study leader explained:
"Grooming is the glue that holds chimpanzee society together. We found chimpanzees that were around humans a lot early in life tended not to do a lot of this behavior, even much later, after they learned to live with other chimpanzees. They just weren't good at maintaining these social bonds, and that was expressed by these lower rates of grooming."2
They also engaged in coprophagy (eating their own poop) and hair plucking, and displayed abnormal movements and body posturing.
For Chimps Raised as Pets, There Are Long-Term Consequences
The research team was especially surprised to discover that the chimps’ lack of social skills lasted long after their experiences as pets and performers were over – years and even decades in some cases.
This study was unusual in that the researchers looked at the chimpanzees’ exposure to humans and other chimps on a continuum. Instead of separating the chimps into two groups – those raised by humans and those raised by their mothers with others of their species – the researchers created their own evaluation tool and called it the Chimpanzee-Human Interaction Index.
It measures the amount of time a chimpanzee spent with humans and with other chimpanzees in early life. Then the researchers asked what an abnormal degree of exposure to humans without any exposure to their own kind does to chimpanzees long-term.
According to Ross:
“This showed that those chimpanzees with more atypical beginnings to their lives, spending much more time with humans than with their own species, tended to behave differently than those that stayed with their family through infanthood.”3
Pet Chimps Often Don’t Make a Successful Transition
Scientists have long understood the importance of the mother-infant bond in primates, but this study is the first to look at how both human and chimp exposure can affect a chimpanzee’s behavioral development throughout life.
It is common for owners of pet and performing chimps to relinquish the animals to zoos and sanctuaries once they become too difficult to handle. The upside would seem to be that the chimps end up in more species-appropriate environments and among their own kind.
However, they often don’t adapt well to their new, more natural surroundings or their group mates. According to Ross:
“One of the startling aspects of these findings is that these behavioral effects are so long-lasting. Chimpanzees which have found new homes in accredited zoos and good sanctuaries continue to demonstrate behavioral patterns that differentiate themselves from more appropriately-reared individuals. As a result, the process of integrating them with other chimpanzees can be challenging, stressful and even dangerous at times.” 4
Chimpanzees have two qualifiers that should make it illegal to own them. Number one, they are an endangered species. Number two, they can pose a health and safety risk to humans. And yet it remains legal to own them in most of the US.
"Chimpanzees are incredibly intelligent and sensitive animals," says Ross. "Denying them access to members of their own species, during the critical infanthood period, results in behavioral outcomes that last a lifetime. Even with the best possible care as adults, they often can't fit in with the other chimpanzees." 5
Hundreds of Pet Chimpanzees in the US Are Living Abnormal Lives
Most arguments against keeping wild animals as pets are made on moral or ethical grounds without much science to back them up. The Fisher Center researchers believe the results of this and future studies will offer a clearer picture of the degree to which the practice of keeping chimps as pets is harmful.
They hope their research will help support the growing body of evidence against laws allowing chimps to be kept as pets, and contribute to changing policies about private chimpanzee ownership.
And this isn’t just about who should or shouldn’t be allowed to own a chimp. According to Ross:
“It also has a lot to do with helping zoos and sanctuaries who have taken in ex-pets and ex-performers understand the special needs of these chimpanzees. The more information we give them about what challenges these chimpanzees face, the better they’ll be able to set up specific management protocols that can make the transition a bit easier.”
Chimpanzees Are Meant to Live in the Wild, Not in Our Homes
Jane Goodall, considered to be the world’s foremost authority on chimpanzees, knows that chimps don’t make good pets. From her website:7
“Chimpanzee and monkey infants are irresistibly cute, and it might seem that raising one would be just like raising a human child. As infants, chimpanzees are affectionate, needy, and a delight to interact with. But chimpanzees grow up fast, and their unique intelligence makes it difficult to keep them stimulated and satisfied in a human environment.
By age 5 they are stronger than most human adults. They become destructive and resentful of discipline. They can, and will, bite. Chimpanzee owners have lost fingers and suffered severe facial damage.
Chimpanzees are meant to live in the wild, not in our homes. Those that have been taken from the forest and their mothers belong in a sanctuary or a high quality zoo. Like human children, ape children learn in a social context, by watching and imitating adults. Chimps that grow up apart from a normal group fail to learn the nuances of chimp etiquette, and are likely to behave abnormally.
As adults, chimpanzees have at least five times the strength of humans – too much for any pet owner to manage! Zoos usually refuse to accept pets because they tend not to fit into established groups. Historically, many pet chimps ended up in medical research laboratories. Today they are likely to end up in a roadside zoo.”
How You Can Help
Thinking about a chimpanzee as a pet? I hope not.
Hopefully the study results discussed above and other information in this article serve as a cautionary tale for anyone who is considering acquiring a chimp as a pet. There’s about a 99 percent chance it won’t end well for you or the animal.
Please don’t convince yourself that you can provide a good life for a primate, and please don’t support or encourage the efforts of those who would tear baby apes from their mothers or breed them for profit.
Please leave these beautiful wild creatures in the wild, or alternatively, in the care of primate experts who can provide a proper natural sanctuary for them.