Getting animals used to the presence of humans is at theheart of the art and science of zookeeping. The key aim is todiminish an animal's flight distance, which is the minimumdistance at which an animal wants to keep a perceived enemy.
A flamingo in the wild won't mind you if you stay more thanthree hundred yards away. Cross that limit and it becomestense. Get even closer and you trigger a flight reaction fromwhich the bird will not cease until the three-hundred-yard limitis set again, or until heart and lungs fail. Different animals havedifferent flight distances and they gauge them in different ways.
Cats look, deer listen, bears smell. Giraffes will allow you tocome to within thirty yards of them if you are in a motor car,but will run if you are 150 yards away on foot. Fiddler crabsscurry when you're ten yards away; howler monkeys stir intheir branches when you're at twenty; African buffaloes react atseventy-five.
Our tools for diminishing flight distance are the knowledgewe have of an animal, the food and shelter we provide, theprotection we afford. When it works, the result is anemotionally stable, stress-free wild animal that not only staysput, but is healthy, lives a very long time, eats without fuss,behaves and socializes in natural ways and – the best sign –reproduces. I won't say that our zoo compared to the zoos ofSan Diego or Toronto or Berlin or Singapore, but you can'tkeep a good zookeeper down. Father was a natural. He madeup for a lack of formal training with an intuitive gift and akeen eye. He had a knack for looking at an animal andguessing what was on its mind. He was attentive to hischarges, and they, in return, multiplied, some to excess.