More and more zoos across the country are following the lead of the Bronx Zoo and replacing their caged animal displays with naturalistic exhibits where animals enjoy much of the freedom they would have in the wild.
The bars have not completely disappeared, even from the finest zoos. But their numbers are dwindling as master plans are developed for exhibits which entertain the public while providing an education about the importance of environmental conservation and wildlife preservation.
"In the old days when animals lived in unnatural settings, visitors didn't have a good feeling in zoos," said Karen Asis, public affairs director for the American Association of Zoological Parks and Aquariums, an organization with headquarters in Bethesda which represents 162 accredited institutions across the country. With the animals living a miserable existence, there's no way to get people to appreciate their natural heritage."
Today, there are state-of-the-art exhibits in zoos large and small from New York to the state of Washington and many points in between. These exhibits simulate habitats with amazing authenticity, re-creating rain forests, savannas and swamps which are populated by a mix of species co-existing peacefully. The animals behave much as they would in the wild, living in family groups and successfully reproducing offspring.
"The new exhibits and the new habitats are helping people to appreciate their natural heritage because they can see the animals living very closely to the way they would if they were in the wild," Ms. Asis said. "That's the best exhibit we can give anyone. I think we are learning to appreciate nature and the environment and what we have to save."
The top zoos in America feature many fine naturalistic habitats. The Seven Seas Panorama at Chicago's Brookfield Zoo is a rocky, outdoor Pacific Northwest shoreline for walruses, seals and sea lions. Dolphins live and perform indoors in a Caribbean beach setting.
Brookfield has one of the world's largest indoor zoo exhibits of mixed species in Tropic World, where visitors are immersed in three separate rain forest regions. Squirrel, spider and capuchin monkeys, golden lion tamarins, two-toed sloths, Brazilian tapirs and a giant anteater live in lush vegetation near a 60-foot waterfall in the South American rain forest.
A mangrove swamp in the Asian rain forest is home to orangutans, gibbons, small-clawed otters and dusky leaf monkeys. And the rugged terrain of an African rain forest is filled with western lowland gorillas, a pygmy hippo and a variety of tropical birds.
This zoo has also united three separate ecosystems in one exhibit -- the Fragile Kingdom. There's an indoor African desert, where meerkats, jackals, naked mole-rats, caracals, rock hyraxes, bats, fennec foxes and bat-eared foxes make their homes underground, in caves, in rocky areas and on the desert floor.
Also part of the Fragile Kingdom is an indoor Asian rain forest inhabited with clouded leopards, fishing cats, giant squirrels and Burmese python. Outdoors is a rocky exhibit for African lions, Siberian tigers, snow leopards, jaguars and Asian leopards.
And Brookfield is nearing completion of the first phase of a project that will transform nearly one-fourth of the zoo into seven African habitats over the next 10 years.
The Elephant Forest at Woodland Park Zoo in Seattle, Wash., incorporates the culture of the Asian pachyderms' native Thailand into a tropical forest habitat. The elephants' shelter is a replica of a Thai temple. The elephants pile and stack logs during daily demonstrations in a Thai logging village. And they enjoy daily baths in an Asian marsh pond, which is so deep that they can completely submerge.
Giraffes, antelope, zebras and monkeys roam the open grasslands in an award-winning African Savanna exhibit. The Woodland Park Zoo also has one of the finest exhibits of lowland gorillas in the country and will add a new troop to incorporate into the tropical rain forest that will open later this year.
The Audubon Zoo in New Orleans is noted for its Louisiana Swamp exhibit -- a "wet forest" filled with cougars, black bears, raccoons, nutria, opossums, otters, herons and egrets as well as some famous and very rare white alligators. And its Tropical Bird House re-creates a rain forest that is a key element in the zoo's highly successful breeding program for rare and endangered birds.
In the past three years, the San Diego Zoo has opened three new naturalistic habitats as part of its 20-year plan to create 10 distinct climate zones in the park. Gorilla Tropics is its most recent addition, an open air exhibit where the gorillas -- including a baby boy born on Christmas Eve -- live near a waterfall surrounded by banana and fig trees.