Sadly this week yet another case of a chimpanzee attacking someone has been reported in the news. This week it was Texas grad student, Andrew Oberle, working at the Jane Goodall Institute's Chimp Eden (apparently the place has its own TV show from what I've heard). I sympathize with Andrew and his family and wish him well.
I spent a couple of years working with Chimps myself, both with common chimpanzees at the Primate Foundation of Arizona (now closed) and bonobo chimpanzees at the Language Research Center (now under another name and relocated in Iowa).
From my work with chimps I learned that they (at least the common chimps) are not mean-spirited monsters bent on hurting humans. However they are mischievous, and by nature are easily swept up in powerful emotions which can lead them to do things--sometimes very violent things--that they may regret later. They are, after all, wild animals.
Thus it was common, though I had a very strong, loving bond with my nearly 80 chimpanzee wards, to have them grab and scratch me--at times rather aggressively. One coworker, on my day off, was even pinned against a cage by a couple of chimps that grabber her, and had a portion of her finger bitten off. If I'm not mistaken, my supervisor had a portion of her finger bitten off before I began working there as well. I was very fortunate to have never received any injuries.
The one thing about common chimpanzees though, is that they are bad liars. Common chimps wear their emotions on their shirtsleeves quite literally. Their mental and emotional state and their intentions can be easily read by their body language, their posturing, the way their hair bristles, their hand and eye motions and their vocalizations--one only needs the training and experience to read them. The problem comes in when we, apparently as Mr Oberle found, do not pay attention to these signs. This is particularly a danger when we ignore safety protocols designed to protect us against human error...
All this being said, I had a very different experience working with bonobo chimpanzees and the likes of Kanzi (a chimpanzee celebrity often featured in National Geographic, Time Magazine, the Discovery Channel and dozens of renowned newspapers). At the Language Research Center I worked under the infamous Dr. Sue Savage-Rumbaugh and her star-studded gaggle of linguistically-gifted bonobos.
I found bonobos (also known as pygmy chimpanzees), unlike common chimps, to in fact be very good liars, and at times devious. These intelligent little beasts have the ability to mask their emotions--and to convey a false mental state in order to deceive--and at times severely harm--those around them.
I did not witness any attacks at LRC myself (though I was scratched and grabbed constantly). However, on my day off, Kanzi escaped his cage and attacked one of the researchers at LRC, biting his groin and shoulder badly, and severing his finger from the knuckle.
The stories I was told by staff--of things that happened before I began working at LRC--were much worse. I was told that the bonobos had a long history of escaping and not only wandering the center grounds, but also the adjacent residential neighborhood on at least one occasion. I was also told that the bonobo chimps had mauled several people, including the maid and another researcher, and causing severe, long-term injury. Again I did not witness these attacks, but it was what I was told by my manager and grad students at the center.
The moral of the story is simple. Regardless of how incredibly intelligent and special chimpanzees are, they remain very dangerous wild animals. Great caution must be used in their care, and they should never be kept as mere pets. Those that wish to work with them must be made aware of the significant risks and take necessary precautions at all times.