In How To Train Your Dragon , which opened on Friday, a Viking named Hiccup befriends a cold-blooded creature called Toothless. By the end of the movie, Hiccup can cruise around on Toothless' winged back with ease. It seems as though it's pretty simple to train a dragon, but what about real-life reptiles? Could you teach a crocodile to beg?
Zookeepers can and do train their scaly charges to move around their cages, to stand still, and to open their mouths on demand. To impart these behaviors, keepers use a method called "target training," in which they teach an animal to associate a "target" (usually a colored disc attached to a stick or a long pole) with an edible treat. Once trainers have achieved association, they can get the animal to move around his exhibit by presenting the target in different locations. They can also train him to stop moving by using a vocal cue—saying "sit," for example. Training a reptile, then, is not too different from training a dog—at least methodologically.
Zoo employees train their animals in order to facilitate care-giving. Teaching a lizard to hold its mouth open makes it easier to administer medicine, while coaching him to stand still makes it possible to draw his blood for medical tests. Animals that can move on demand are easier to transport. Interacting with trained reptiles is also safer for the keepers.
Although it's possible to teach reptiles more complicated behaviors—crocodiles can learn how to swim through hoops, for example, and at least one turtle knows how to shake hands and roll over —they're more difficult to train than mammals or birds. That's partly because reptile brains are less complex. Also, since big reptiles eat much less often than mammals and birds, training them to respond to edible rewards is a lengthier process. It's hard to motivate herbivorous reptiles like tortoises as well, since they're not used to the concept of working hard to find food. (Grass is readily accessible.)
Thanks to Jim Murphy of the National Zoo, Patrick Thomas of the Wildlife Conservation Society's Bronx Zoo, and Crystal Crimbchin of the Columbus Zoo and Aquarium for passing on their reptilian knowledge.