In October 2009, Karen Pryor came to Denver to lecture and share her expertise in animal behavior and training with the keepers at the Denver Zoo. Angela Eaton was invited to shadow Karen as she toured the zoo and consulted with the keepers. Karen also talked about her many experiences that led to her latest book, Reaching the Animal Mind.
Many keepers at the Denver Zoo already use operant conditioning with event markers (clicker training) to teach behaviors for medical exams, to keep the animals and zookeepers safe, and to enrich the lives of captive animals.
An ostrich has 4-inch claws on each foot, so its feet are very dangerous. To prevent injury to keepers at the zoo, the birds are taught to sit, which immobilizes their claws. The most effective way to teach them to sit on cue is through operant conditioning. “Using a whistle as an event marker, the ostrich’s movements are shaped” until it is in a sitting position – in other words, each time the bird approaches or approximates sitting, the behavior is marked with the whistle and the ostrich is rewarded, until eventually, the bird sits.
Prior to clicker training, veterinarians used to dart zoo animals to sedate them for exams or other procedures. Using clicker training, zookeepers teach animals to respond to cues that are specifically used for medical exams - like the “blood draw behavior.” The animal is taught to sit or stand in a comfortable position while the keeper inserts a needle to draw blood.
Rhino’s have always been considered dangerous, especially in captivity. They were historically darted with drugs to subdue them for exams or to move them. This caused the animals to associate the keepers with darting, so they would thrash about when they were approached, injuring themselves and damaging their enclosures. Clicker training has changed that dynamic. Watch the video on the right to see how calm this Rhino is and all the behaviors he can perform on cue.
In the video on the right, a Rhino stands calmly while his blood is being drawn. A zookeeper cannot use force or coercion to train a large animal like a Rhino to stand still and be calm. Clicker training encourages the animal to willingly submit to the blood draw.
Gerenuks belong to the same family as the antelope. They are elegant animals with dramatic markings and long, thin legs. A consequence of being fast and nimble in captivity is that they’ll run into fencing and hurt or kill themselves when frightened, making it difficult to keep them safe in captivity. At the Denver Zoo, the keeper has captured the Gerenuk’s natural behavior of using its front legs to stretch against a tree trunk and eat leaves by using a whistle to mark this behavior. In this video, the zookeeper is able to draw blood and do a full body exam while the animal is relaxed, even when it’s in the public viewing area in front of the crowd! Play the movie (9MB)
