 |
Animals Make Us Human: Creating the Best Life for Animalsby Dr. Temple Grandin and Catherine Johnson
Houghton-Mifflin Harcourt, New York, NY, 2009 (In United Kingdom, book title is "Making Animals Happy" and ISBN is: 978-0-7475-9714-8) Links for ordering: |
The reason the zoo called me was that they’d read Animals in Translation and they’d done everything the book said to do, but their animals were still going crazy. They couldn’t figure it out.
So I went to the zoo and talked to the keepers. They said they thought the problem had to be something to do with novelty, but there wasn’t anything new in the alley, and they couldn’t see anything different about the days the antelopes walked calmly through the alley versus the days they balked. They’d been over it and over it. Everything in the alley had always been in the alley and was still in the alley on the balky days.
I went in and took a look. The keepers were right. There wasn’t anything new inside the alleyway.
The problem turned out to be that there was something old in a new position. The alley was enclosed by a chain-link fence with an electric box mounted on it that was supposed to have a warning sign attached to its side. However, the employees didn’t have the screws to put it up, so they’d just leaned the sign up against the fence down below the box.
The sign wasn’t very stable propped up like that, and on some days it got knocked over. That was the problem. The front of the sign was black and white, and the back of the sign was bright yellow. When the sign tipped over, the yellow back was showing. Yellow really attracts an animal’s attention. That’s because the only animals that have full color vision are primates and birds. All the rest have dichromatic vision, which means that they see two main colors — bluish purple and yellowish green — and they don’t see red. Anything yellow in the environment will “pop;” they’ll notice it right away. Every time the sign got knocked over, the yellow back was visible on the ground and the antelopes reacted.
The fact that the sign was out of place was probably even scarier. Most days the sign was in its proper spot, leaning up against the fence. That’s where the antelopes expected it to be. Then all of a sudden it would be lying on the ground and it would be yellow, too. That’s a big change for an antelope. The reason the humans didn’t pick up on it was that to humans a sign is a sign. It’s so hard for normal people to think like animals. A good analogy would be if you started to walk into your living room and you saw that the sofa had been turned upside down and spray-painted a different color. That would definitely scare you.
Within a species, different individuals have different hyper-specific fears, too. Most fears are learned, so different zoo animals with different histories can acquire different fears over the years. Those fears are going to be hyper-specific because they are stored in the animal’s memory as pictures or sounds. Usually the animal is afraid of something neutral that it was looking at or hearing when the scary event occurred, which makes it even harder for the human keepers to analyze. I saw a case of an elephant who feared the sound of diesel engines because he had been shoved around by a big tractor. Car engines did not bother him. Fortunately, in that case the keepers knew what the problem was and knew to keep diesel-powered equipment away from him.
The only way to deal with hyper-specific fears is to figure out what exactly is scaring the animal through close observation. Once you identify the frightening person or thing, you have two choices: try to habituate the animal to the object or remove it from the animal’s environment. If the object is something easy to eliminate, then eliminate it. But if it is a common object like a white shirt, habituation is recommended because we cannot rid the world of white shirts. Getting an animal over its fears is easier in the less flighty species.
The idea that you can train high-fear flight animals to cooperate with veterinary procedures was new when I first started working on it. About ten years ago the nutritionist for the Denver Zoo, Nancy Irlbeck, wanted to do a study to determine how much vitamin E the zoo’s four nyalas had in their blood as part of a larger study of their nutritional health. (Nyalas are a small South African antelope.) The trouble was that stress suppresses vitamin E levels, so if you stress the animal it’s impossible to get an accurate reading.
Nancy called me and asked, “How do we get a no-stress blood sample out of an antelope?” I told her there’s only one way: You have to train the animal to voluntarily cooperate during the blood test. There’s no other way to do it.
People thought that was crazy. Nyalas are super-shy, and people who knew what they were like were saying, No, no, no, there’s no way to train these animals, because they will go berserk and kill themselves while you’re trying to manipulate their behavior.
Oh yes, there is. I worked with some great students, and we trained those animals to stand still calmly while a lab technician drew blood.
The secret to working with a high-fear prey animal like a nyala antelope is to start with a very long habituation phase. Before I could even think about training the nyalas to go inside a wood box and hold still for a blood test, we had to spend ten days just getting them used to the sound of the wood door sliding tip and down. The first day we could move the door only one inch because if we’d moved it any more, that animal would have gone splat on the wall. That’s what people were worried about: that we’d startle the animal, and it would kill itself in its panic.
The other danger we had to worry about was the fact that hyper-flighty animals can form fear memories so strong that they never get over them. If we had let them panic just once at the start, that could have made it impossible to train them.
We quickly discovered that the key to successful habituation of a high-fear prey animal is to never push the animal past the “orienting” stage. Orienting is what animals or people do when they hear a new sound or see something strange. They stop what they’re doing and look toward the new thing. During the orienting stage, a high-fear animal makes a split-second decision: “Do I panic and run, or do I keep looking?” The choice is either to SEEK or to allow FEAR or RAGE to take over.
I think it’s possible that prey species animals have a much faster path between orienting and FEAR than non-prey species animals. One time when I was driving on the freeway a big two— by-six board slid off a trailer just ahead of me in the next lane over and came flying diagonally across the road in my direction. My attention locked onto the board like radar, and it was as if everything slowed down. The board looked like it was floating on the road toward my car. My driving became super-controlled and I moved over to the breakdown lane where the board slid on the ground so I could straddle it between my front wheels. During this time I was in a state of pure concentration with no emotion. As soon as I realized I was safe, my FEAR system switched on and I felt terrified, but not until that moment. If I had panicked the instant I saw the board coming at me, I would have had a horrible accident.
I’ve never seen a prey species animal do anything like that. High-fear prey animals go straight to terror if you push them past the point of orienting to novel stimuli, and they can hurt or even kill themselves in panic. So we stopped the habituation program the instant an antelope oriented to what we were doing. When we moved the door one inch on the first day and the antelopes oriented to the sound, we stopped the program for that day. On the second and third days, we opened the door a few more inches. The animals oriented, and we stopped for the day. It took ten days altogether to habituate the antelopes to the door being opened. By then we could yank the door open quickly without drawing the animals’ attention. They didn’t orient no matter how far or how fast we opened the door.
At that point we could begin a combination of training and habituation. We used special yummy treats to lure the antelopes inside the box, and we stopped work whenever they oriented to some aspect of the box or the training.
We spent fifteen minutes a day for weeks training them to go in the box, keep their legs still, and let us get a blood sample out of their legs. We used no sedation or drugs of any kind. People were amazed. The only way anyone had ever been able to get blood work done on the big prey animals was to shoot them with a tranquilizer dart gun and collect the specimens while the animals were unconscious. Zoos were darting their animals at least once a year, and it was horribly traumatic. I’ve talked to one zoo vet after another who has done lots of darts. Many end up quitting because the animals hate them so much.
Even after we finished training the antelopes, the veterinarian who had darted them in the past was never able to handle them. A strange vet could examine them, but not the dart gun man. They recognized his voice, his appearance, and his gait. These animals aren’t just afraid, either. They’re angry. They hate the mean, nasty vet who does all the horrible procedures.
Zoos don’t dart all their animals, just the big ones. To do procedures on the smaller animals they physically restrain them, which is just as terrifying for the animal as being darted. With a small animal, like an otter, a keeper catches the animal with a fishnet and then holds it down until the vet is finished. To restrain a medium-sized animal like an antelope, the keepers take a big sheet of plywood and crowd the animal up against a wall in the barn and hold it there. Using restraint triggers RAGE, and the veterinary procedure triggers FEAR, so the smaller animals hate the vet as much as the big animals do. We still had to be very careful after the antelopes were fully trained. The nyalas were mostly female, and they were Miss Hyper-Specific. If you trained them to tolerate one thing and then you deviated from that one thing, they panicked. One day there were some men fixing the roof of the barn where the nyalas slept at night, and the antelopes freaked out and slammed into the chain-link fence. Fortunately they were OK. They panicked because they had learned that people in front of their exhibit were safe and also that people inside the barn were safe so long as the dart gun vet wasn’t there. But people on the roof were something totally new and scary.
The zoo was happy with our results, so they decided to train their bongo antelopes next. I trained the student trainers. While I was working with the students I had an idea. There was a keeper at the zoo, Megan Phillips, who was in charge of collecting blood from the antelopes once a month whether they needed it or not just to keep them trained to the procedure. One day I said, “Megan, what are you doing with that blood?”
She said, “We just put it in the freezer.”
So I told her, “Send some of that blood to the lab and get a glucose, CPK, and cortisol done and send the bill to me.” Glucose, CPK, and cortisol are all related to stress, and stress hormones weren’t part of the study. I decided to tack on a cortisol test because the blood was already there, stacked up in the freezer. The levels came back incredibly low, almost at the level of cattle that are asleep, even though each animal had stood in the blood-testing box for twenty minutes. The scientific literature had values from netted or darted animals that were three and four times higher than what I got in our trained animals. Researchers were calling those elevated values “normal” because everyone always got those values when they drew blood from captive antelopes. But the reason everyone always got those values was that everyone was drawing blood from terrified animals.
That’s one of the big problems in zoo and wildlife veterinary medicine. A lot of people who work with wild species don’t understand that if you throw a fishnet over an animal and hold it down so you can get blood drawn, you stress the crap out of it. I’ve had people tell me, “It can’t be that stressful; we just hold them down for thirty seconds.” I say, “Yeah, a mugging on the subway only takes thirty seconds, and it’s real stressful.” Training the animals to cooperate with veterinary procedures is much more humane.
We wrote up our results in a paper we called “Low-Stress Handling of Bongo” and submitted it to a journal. One of the reviewers objected to the title. He said Low-Stress Handling of Bongo” was judgmental because it implied that the regular methods of drawing blood were stressful for the animals — which they were. We had to change the title to get the article published. We finally called it “Crate Conditioning of Bongo (Tragelaphus eurycerus) for Veterinary and Husbandry Procedures at the Denver Zoological Gardens.”
We eventually got them so well trained that a student could walk right up to an antelope and stick an IV into its jugular without the slightest resistance from the animal. We didn’t need a blood-testing box. Then one of the pronghorns got sick and needed an antibiotic shot in the shoulder, not the neck. When that same student tried to give the shot, the antelope went berserk. It had been trained for “IV in neck;’ not for “shot in shoulder;’ and it hadn’t developed a general category called “getting a shot.’ The antelopes’ hyper-specific brains detect and react to small differences.
On the other hand, the pronghorns had developed some general categories for small neutral objects. I noticed that they had no reaction to novel coffee cups or drink bottles trainers carried into the enclosure. They had seen so many different drink containers that they had probably opened up a new file folder in their brains labeled “small things in people’s hands are safe.”
They were much more fearful of large novel objects compared to small novel objects. We had to introduce a new piece of plywood or a large chest very carefully to avoid a crackup on the fence. One of the reasons large objects are scarier is that the predators that eat the pronghorns are large. The pronghorns are naturally more inclined to acquire a fear of big things.
We didn’t use any negative reinforcement or punishment at all when we trained the antelopes. We couldn’t. It would have wrecked them the way sacking out a horse wrecks an Arab horse. Negative reinforcement and punishment have always been used by some trainers with big, not-so-fearful animals like elephants that can take a lot of abuse without panicking or getting sick the way a dolphin would. It’s still a bad idea with those animals, because elephants never forget, and elephants that have been abused in the past may attack a trainer. But you can get away with it. Using either negative reinforcement or punishment with a high-fear animal will destroy any chance you have of training that animal to cooperate.
Click here to return to the Homepage for more information on animal behavior, welfare, and care.