In February 2009, a 200-pound pet chimpanzee named Travis attacked a 55-year-old woman, Charla Nash, tearing off her nose, eyes, and lips. Nash, a friend of Travis’s owner, a Connecticut woman named Sandra Herold, had driven over to help calm the “rambunctious,” 14-year-old chimp, as Herold later told detectives. Police called to the scene shot Travis, who disappeared into the surrounding woods and was later found dead.
According to a New York Times article published soon after the attack, Herold had raised Travis “almost as one of her own children,” and his social skills included “drinking wine from a stemmed glass, dressing and bathing himself and using a computer.”
Acquiring such human habits may be considered by some to be quite extraordinary for a chimp, but a new study shows that chimpanzees raised as pets or performers are significantly impaired in the social and sexual skills that enable them to function normally within their own primate communities.
Hani D. Freeman and Stephen R. Ross, animal behaviorists at Lincoln Park Zoo in Chicago, used a handheld digital device to document almost 1,400 hours’ worth of activities in 60 chimpanzees living in sanctuaries and in zoos accredited by the Association of Zoos and Aquariums. Thirty-six of these animals were former pets or performers. Some had been “essentially raised as humans,” as personal pets in private homes, “with related traditions such as eating at a table and wearing clothes,” and had little exposure to their own species early in life. Others, trained as performers, had spent some part of their early years with other chimps, but were also “highly exposed” to human trainers and audiences.
Freeman and Ross found that, depending on their earlier interactions with humans, there was a significant difference in the amount of time the chimps engaged in a variety of innate behaviors. Those that had spent their youth with members of their own species spent more time grooming other chimps than those raised with humans, for example. They also engaged in more frequent sexual activity. These behaviors, the authors write, are important elements of chimp social dynamics; the absence of them can have deleterious long-term effects. Several studies, they note, show that primates reared with humans have lower rates of reproductive success, possibly due to their atypical sexual behavior.
The authors say the study provides the first empirical evidence of long-term, negative effect of private ownership on chimp welfare—evidence that should inform legislation designed to protect chimps and other, threatened animals, as well as humans who come into contact with them. Travis’s victim, Charla Nash, for one, is a driving force behind such legislation. After undergoing one of the first face transplants in the United States, she has become a strong advocate for the Captive Primate Safety Act, which, if enacted, would prohibit the transport of chimpanzees, monkeys, and other primates across state lines for the exotic pet trade.
Even so, it is still possible in some states (including Idaho, Nevada, and North Carolina) to buy wild animals such as chimps, and even lions and tigers, without any kind of license or permit. That is why Ross of the Lincoln Park Zoo believes that there is a strong need for stricter federal legislation regulating ownership of chimpanzees and other primates.
“We’ve known for decades now about their extremely advanced psychological needs and dynamic social behavior, and both of these characteristics make them unsuitable pets,” he wrote to me via email. “Thanks to the events in Connecticut several years ago, people have become aware of the public health and safety risk they present as well. Yet today there remain chimps in private homes across the U.S. and a continuing legal trade in this species. We [are] way behind most of the rest of the world in this regard.”