Zoological Parks

Protected Environments

In the late 1800s, a German animal dealer, Carl Hagenbeck, first envisioned the modern zoo. His dream was to create a spacious zoological park where animals could be seen in something resembling their native habitat. His park was built in 1907, near Stellingen, Germany, with no fences. Different species such as lions and zebras were kept in the same enclosure, separated by deep moats. Despite commercial popularity, Hagenbeck's ideas did not catch on until the mid-1900s. Animal behaviorists began to emphasize the importance of giving captive animals enough room for some activity and allowing social animals such as monkeys to be in the same cage. They concluded that animals kept in such environments would be healthier, more active, and more interesting to the paying public.

Worldwide, unspoiled habitats began disappearing at an alarming rate by the late twentieth century, as did their inhabitants; more and more wild animals became increasingly rare. Many larger zoos transformed from competing fiefdoms into cooperating members of zoological organizations whose mission became wildlife conservation, research, education of the public, and captive breeding of endangered species.

Disagreements Over the Best Strategies

As populations of some species plummet because of habitat destruction, illegal poaching, pesticides, and pollution of air and water, conservationists in the United States divide along two lines of thought. The first, which includes the Sierra Club and Friends of the Earth, believes that animals must be protected and saved in their own habitat, that a species is not saved unless it continues to exist in the wild. The second group is led by the U.S. Fish and Wildlife Service, the National Audubon Society, and the American Association of Zoological Parks and Aquariums. They believe that endangered species must be brought into zoos and wildlife parks where new generations can be raised, frequently with much human intervention, and then released back into the wild. Many zoos participate in species survival plans (SSPs), which coordinate breeding efforts for more than fifty species, including cheetahs, rhinoceros, Asian elephants, orangutans, pandas, Puerto Rican crested toads, tamarins, zebras, tapirs, lemurs and Komodo dragons. The long-range goal of the SSP program is to build up large enough populations so that these animals can be returned to their natural habitat. A central computer system, the International Species Inventory System, keeps detailed records of the genetic background of the animals in the program. In order to avoid inbreeding depression, which can cause weakened resistance to disease and infertility, animals may be shipped from one part of the world to another to arrange genetically diverse matches. Ultimately, even this tiny gene pool will need to be replenished from the wild to stay vital.

Captive breeding programs have had mixed results. Some species respond well and others, for reasons not yet understood, but probably related to psychological stress, refuse to breed in captivity or, after birth, abandon their offspring.

New Ideas for Zoological Parks

At the beginning of the twenty-first century, zoos are moving in several directions. As local wild habitats vanish, some small zoos are specializing in local wildlife, providing a glimpse of how indigenous plants and animals interact. Large wildlife parks incorporate hundreds of acres of bogs, woods, meadows, and grasslands and feature native and exotic species that thrive in local conditions. These parks are frequently driven through or have walking trails where people are inobtrusively separated from the animals.

Some zoos have become "bioparks," using aerial walkways, watery moats, and one-way security glass to offer visitors the opportunity to see animals in something resembling natural conditions. These immersion exhibits are sometimes huge re-creations of specific ecosystems. Amazonia, at the National Zoo in Washington, D.C., is a 1,400-square-meter (15,000-square-foot) dome filled with thousands of tropical plants, fish, birds, insects, reptiles, amphibians, and mammals. With careful attention to temperature and humidity, it offers a taste of a real tropical jungle. Other immersion exhibits include replicas of Antarctic penguin islands and sandy deserts. Moonlight houses have also become common in many zoos. In these buildings day and night are reversed. Infrared lighting allows people to view nocturnal species who rest during the day and are active at night. In large enclosures that have artificial caves and tunnels, bats fly about in search of fruit, nectar, and insects. Desert animals emerge from burrows, coyotes stalk and howl, raccoons hunt for food to wash beside streams, and crocodiles and alligators wallow in marshes before setting off in search of dinner. As people live increasingly urbanized lives, they are looking for zoos to provide a way to get closer to nature and an experience of the wild.

Modern zoos are extremely expensive operations. It is a massive undertaking to meet the daily nutritional needs of hundreds of animals of different species. The food must be as appropriate as possible to each animal and delivered in a way that mimics its natural eating habits. Carnivores need whole animals or large chunks of meat and bone. Primates need to search out fruits, nuts, and seeds that have been hidden in their enclosures. Each elephant requires 45 kilograms (100 pounds) of grass and 14 kilograms (30 pounds) of vegetables a day. Live worms, crickets, guppies, lizards, and mice are all kept on hand for specialized appetites. And some herbivores need specific leaves from their homes: acacia for giraffes, eucalyptus for koalas, bamboo for pandas, and hibiscus for leaf-eating monkeys. Abandoned or orphaned infants require precise formulas and extensive care. Some baby birds need to be fed every few minutes to survive.

In nature, sick or injured animals die swiftly. In zoos, each animal represents such a costly investment that most major zoos have full-time medical teams to diagnose and treat disease and provide preventive health care. Tigers and gorillas get dental checks. Females are tested for fertility and carefully monitored during pregnancy. New animals and sick ones are quarantined, and surgeries are performed on broken limbs or tumors.

Naturalistic zoo exhibits attempt to recreate the environment of a given species. This involves scientists, designers, architects, and curators. The exhibit must take into account every detail of each animal's life: breeding, social interaction, exercise, and the food gathering method for which the animal is genetically designed. The insects, plants, and geologic features need to be recreated. Careful regulation of temperature, humidity, and the length and variation of daylight needs to be maintained. The amount of effort involved in recreating even a small ecosystem is beyond the capability of all but the largest zoos.

Although one of the stated goals of zoos is to replenish wild populations, almost no animals have ever been returned to their native habitat. Restoring wild animals is difficult, expensive, and requires the cooperation of the local people to succeed. Craig Hoover, program manager of the Wildlife Trade Monitoring Arm of the World Wildlife Fund, stated that "Zoos have been very successful breeding grounds for many species. But what do you do with those animals when they're not babies anymore? Certainly the open market is the best place to sell them" (Merritt 1991, p. 32). And dozens of major zoos admit to supplying the multibillion dollar a year trade in exotic animals, where rare and endangered species wind up in the private collections of celebrities or as trophy targets on profitable hunting ranches.

Critics of zoos contend that while zoos justify their existence by claiming to educate children, they are teaching the wrong lesson: that it is acceptable to keep wild animals in captivity. Nor is warehousing animals the answer to saving them from extinction. The ultimate salvation of endangered species is in protecting their natural habitats. Perhaps the future of zoos lies in the vision of the Worldlife Center in London, a high-tech zoo with no animals. Visitors observe animals via live satellite links with the Amazon rain forest, the Great Barrier Reef off Australia, and the African savanna and jungle. Rather than putting money into all the infrastructure of a modern zoo, it goes directly to habitat protection to developing nonprofit sanctuaries where hunters and poachers are kept at bay and through which the local people are given an economic incentive to participate in wildlife preservation.

The greatest contribution that zoos may have made is to highlight how little humans understand the incredibly intricate mechanisms of life on Earth. Human technology, while capable of destroying vast ecosystems, is insufficient to create and maintain them. Zoos began as a symbol of human conquest of wild animals. Perhaps modern zoos can serve as sanctuaries for animals rescued from ill treatment and as reminders to be more respectful of nature and the place of humans in it.

SEE ALSO HABITAT LOSS; HABITAT RESTORATION; NATURAL SELECTION; POPULATIONS; SELECTIVE BREEDING.

Nancy Weaver

Bibliography

Challindor, David, and Michael H. Robinson. Zoo Animals: A Smithsonian Guide. New York: Macmillan, 1995.

Merritt, Clifton. "Low Class, No Class Scumballs." Animals Agenda 11, no. 10 (1991):32.

The Zoological Society of San Diego has developed a different and engaging interface for accessing information on its web site. This new site is titled "E-Zoo," and is available at <http://www.sandiegozoo.org/virtualzoo/homepage.html>. Between the interactive games, the videos, and the e-postcards, the Zoological Society has helped to make learning about animals fun from any location— even your desk chair.