The Welfare of Zoo Animals
Zoo Animals' Behavior: Is it Normal?
Stereotypical behavior in an animal is any repeated unnatural action done in response to boredom, stress, or general unhappiness. It can involve pacing back and forth, swaying from side to side, or even mutilation or self-harm. Because mentally insane humans exhibit similar behavior, some individuals have gone so far as to say animals acting in such a way may also be mentally unstable.
The Causes of Strange Behvior
There are many things that drive animals to perform stereotypical behavior. Among these is the housing of animals in small confined spaces that prevent them from free movement or exercise. Zoos around the world give captive lions 18,000 times less roaming space than is used by their wild counterparts. Therefore, it should come as no surprise that an Oxford University study calculated that lions in zoos spend almost half of their time pacing back and forth, aimlessly.
However, this may be more than just a response to inadequate room. It may also be because of the predators' inability to hunt and capture their prey, a pursuit which keeps them challenged and fully occupied in the wild. Supplying captive animals with ready-made meals denies them a chance to express their instincts and engage in the complex task of finding food. As a consequence, they become bored and restless.
Further, humans cannot always provide animals with their unique dietary requirements. An imbalance of nutrients may cause deficiencies or excess and result in several problems. Zebras in zoos are often overweight because the grass they eat is more energy-rich than grasses native to the African savannah.
A scientist who studied wild gorillas extensively with Diane Fossey claimed to have never seen one vomit, and further, never to have heard of anyone else who had. The Captive Animals’ Protection Society has filmed footage of gorillas housed in zoos not only vomiting but afterward eating the regurgitated food.
Animals may live with only a few companions for various reasons, including limited resources. The co-inhabitants they do form bonds with may then later be transferred elsewhere to relieve overpopulation. Therefore, some social animals suffer as they don't have the companionship or diversity of interaction they require.
Animals that favor seclusion are similarly unhappy as they are displayed daily for the benefit of an audience. One zoo conducted a study of gorillas’ behavior and found that the gorillas showed an increase in agitated rocking, aggression, and grooming when observed closely by large crowds.
Some Zoos Help Their Animals Where They Can
While none of these problems can be completely resolved, some zoos do take measures to provide their animals with a more natural existence. However, space is among the most limited of resources and will continue to be problematic. There is simply no practical way to expand the space of lion enclosures 18,000 times or the space of polar bear enclosures 1 million times, as is considered representative of their normal range. As a consequence, animals will remain in smaller environments than are ideal.
However, zoos can prolong food-seeking and gathering behavior, which in the wild generally consumes most of the animals’ day. Food may be scattered around an enclosure instead of placed directly in front of them. Sometimes it is even hidden or concealed in a box or bag. This provides more of a challenge, as animals must engage in several attempts before they can successfully access a meal. The food itself may also require work, such as an unshelled coconut or fully leaved branch. These necessitate slow and methodical processing.
Nutritionists are employed at zoos to provide animals with the most nourishing foods. However, whether meals are correctly balanced is limited by human knowledge. The gorillas mentioned earlier may be regurgitating their food because they are not receiving a necessary staple in their diet. Another possibility is that they are forced to eat unusual food combinations that their stomachs cannot easily tolerate. As the Philadelphia Zoo website states, feeding monkeys unique varieties of foods is a concept about which they are “still learning." Their enrichment programs focus a great deal on “creating variety” during feedings. Unfortunately, some combinations may be less than ideal.
Further, resources are a problem. Although zebras do eat grass, they eat a specific type that has a different composition from grasses found on non-African continents. This cannot be easily corrected as it is impractical to grow a field of African plant life within a zoo enclosure for a variety of reasons. In addition to climate and seasonal differences, the introduction of foreign plants is controlled in the interest of protecting native species from cross contamination or extinction.
Some zoos ensure that social animals are housed in group settings. Similarly, they separate animals that are naturally alone or that fight upon contact. They may even design safe hiding places for species that prefer to remain elusive. However, since the point of the zoo is to display animals to the public, there will always be a human presence, as well as a way to see into enclosures. They may be allowed the opportunity to hide and escape from human “predators,” but it must still be stressful for animals to be constantly surrounded by them.
Further Zoo Animals Information: Can They Thrive Outside of Nature?
Zoos can and have taken steps to improve the quality of life of their animals. But there is only so much they can do. Animals will likely continue to have limited movement, social interactions, food sources, and foraging opportunities.
Perhaps for these reasons, studies have found that zoo's elephants engage in abnormal behavior twenty-two percent of the time. Bears pace agitatedly back and forth for thirty percent of the time they are on display. Chimpanzees taken from zoos and placed in sanctuaries had hands covered in scar tissue from repeated chronic gnawing. Improvements to zoos are therefore necessary for the sake of the animals.
Unfortunately, they will always fall short of what should be provided by nature.
Zoos and Animal Welfare
Christine Van Tuyl, Book Editor
Christine Nasso, Publisher
Elizabeth Des Chenes, Managing Editor
Farmington Hills, MI: Gale Cengage Learning, 2008.