Yet there will always be animals that seek to escape from zoos. Animals that are kept in unsuitable enclosures are the most obvious example. Every animal has particular habitat needs that must be met. If its enclosure is too sunny or too wet or too empty, if its perch is too high or too exposed, if the ground is too sandy, if there are too few branches to make a nest, if the food trough is too low, if there is not enough mud to wallow in - and so many other ifs - then the animal will not be at peace. It is not so much a question of constructing an imitation of conditions in the wild as of getting to the essence of these conditions. Everything in an enclosure must be just right - in other words, within the limits of the animal's capacity to adapt. A plague upon bad zoos with bad enclosures! They bring all zoos into disrepute.
Wild animals that are captured when they are fully mature are another example of escape-prone animals; often they are too set in their ways to reconstruct their subjective worlds and adapt to a new environment.
But even animals that were bred in zoos and have never known the wild, that are perfectly adapted to their enclosures and feel no tension in the presence of humans, will have moments of excitement that push them to seek to escape. All living things contain a measure of madness that moves them in strange, sometimes inexplicable ways. This madness can be saving; it is part and parcel of the ability to adapt. Without it, no species would survive.
Whatever the reason for wanting to escape, sane or insane, zoo detractors should realize that animals don't escape to somewhere but from something. Something within their territory has frightened them - the intrusion of an enemy, the assault of a dominant animal, a startling noise - and set off a flight reaction. The animal flees, or tries to. I was surprised to read at the Toronto Zoo - a very fine zoo, I might add - that leopards can jump eighteen feet straight up. Our leopard enclosure in Pondicherry had a wall sixteen feet high at the back; I surmise that Rosie and Copycat never jumped out not because of constitutional weakness but simply because they had no reason to. Animals that escape go from the known into the unknown - and if there is one thing an animal hates above all else, it is the unknown. Escaping animals usually hide in the very first place they find that gives them a sense of security, and they are dangerous only to those who happen to get between them and their reckoned safe spot.